初中物理备课教案大全
-
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4, the rig
ht to
confide
ntiality in the
com
pany ar
chives;
5, the rig
ht to the assessment of
de
partments; 6, request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction,
evaluati
on, ma
nagement
reg
ulations, and t
he
company'
s financial and material
management. Main functi
ons: 1, common
functi
ons, in
charge of the
a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n charge of the department
s
and agencies
post functi
ons,
running
processe
s, the
development
of
assessment
methods a
nd
a
ssessment w
ork; 5,
responsi
ble for
the
目录
第一章、
声现象
................................................ .................................................. ........
2
第二章、光现
象
......................................
..................................................
....................
4
第三章
物态变化
................................................ .................................................. ........
7
第四章
电流和电路
< br>............................................... .................................................. ...
1
0
第五章
电阻及欧姆定律
.............................................
...............................................
1
7
第六章
电功率
.................................................
..................................................
.........
2
3
第七章
电与磁
.................................................
..................................................
.........
2
5
第八章
信息传递
................................................ .................................................. ......
2
7
第九章
多彩的物质世界
.............................................
...............................................
3
0
第十章
熟悉而陌生的力
.............................................
...............................................
3
6
第十一章
力与运动
< br>............................................... .................................................. ...
4
0
第十二章
机械与人
< br>............................................... .................................................. ...
4
2
第十三章
压强和浮力
..............................................
..................................................
4
5
第十四章
功和机械能
..............................................
..................................................
5
0
第十五章
小粒子与大宇宙
............................................ ............................................
5
4
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementatio
n, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
s
ector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
nation and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
D
epartment'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be
filed into
t
he work
; 19, is
i
n charge of the
De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23
to
初中物理备课教案
第一章、
声现象
【教学目标】
1
．声音是由物体振动发生的
2
．声音的传播
3
．声速及有关计算
4
．乐音的三要素
5
．噪声的危害与控制
6
、通过构建知识框架和网络，使学生牢记基础知识，掌握分析问题的方法。
【呈现形式】
上述考点常以填空和选
择题型出现。
主要考查学生对概念规律的记
忆和运用所学知识来
解决日常生活中的现象的能力。
【授课形式】
实验教学；实例教学；识记教学；例题教学；教材展示教学等
【知识结构】
一、声音的产生与传播
1
．产生原因：振动（举例：讲话时喉咙的振动；吉他）
< br>2
．传播需要介质：声音可以在
空气
中传播，但不能在真空中传播，物体振动产
生的声音在固体、液体、气体以波的形式
传播。
（举例：敲击桌子能听到声音）
3
．声速：
340m/s
（没有特别
提示的情况下都视为该速度，作为常识识记）
4
．
回声现象及其利用：
（
1
）
传播过程中遇到障碍物会反射回来形成的声音；
（
2
）
回声的区分与加强；
（
3
）回声测距离及其它应用。
二、乐音的三要素
1
．音调：声音的高低，由声源的振动频率（快慢）决定。
（
举例：吉他或翻书）
2
．响度：人耳
感觉到的声音的大小，与声源的振幅有关。
（一个人的声音大小）
3
．音色：发声体的声音品质，由发声体本身的特征决定。
（两个人声音不同）
三、乐音和噪声
1
< br>．区别：
（
1
）从物理学角度看
（有规律或无规律；好听悦耳或难听刺耳）
；
（
2
）
从环境保护角度看（是否污染环境）
。
2
．减小噪声的途径：
（
1
）在声源处减弱―消声（消声器）
；
（
2
）在传
播过程中减
弱―吸声；
（
3
）在耳朵处减弱―隔声（戴耳机）
四、超声与次声
通常把高于
20000Hz
的声音称为超声（具有很强的穿透能力）
，低于
20Hz
的声音称为次声（人耳不能听到）
。
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for the
【真题大练兵】
（
2009
年）
1
．下列数据中最符合实际的是
(
)
A
．一节
新干电池的电压为
1
．
5 V
B
．今天
教室内的气温约为
60
℃
c
．光在
真空中的传播速度为
340m/s
D
．对人体的安全电压为不高于
220
V
2
．遇到大风的天气，路旁架设的电线会“嗡嗡”地响，这
种声音是由于电线
而产生的。
3
．
乐音有三个特征，
音调是反映声音
的，
响度是反映声音
的，
我们通过声音区分不同乐器是靠
。
4
．将手
表放在枕头下面，隔着枕头能够清楚第听到手表“滴答”声，这说明枕
头的传声能力比空
气
。
5
．拿一张硬纸片，让它从一木梳上很快地划过去，再让它慢一点从
同一木梳上
划
过
去
，
两
次
用
力
大
小
一
样<
/p>
，
则
两
次
发
出
的
声
音
〔
A
〕
A
．音调不同
B.
响度不同
C.
音色不同
D.
前三项都不同
< br>6
．医生用听诊器可以清晰地听见患者心跳的声音，这是由于
〔
B
〕
A
．
听诊器能自动收集有用的声音
B.
听诊器减少了声音的分散，
增大了响度
C.
听诊器减少了噪声的干扰
D.
听诊器靠固体传声效果好
第二章、光现象
【教学目标】
1
．光的直线传播
2
．光在真空中的传播速度
3
．光的反射定律，会完成反射光路图
4
．平面镜成像及其特点
5
、光的折射定律，会完成折射光路图
6
、光的色散
7
、透镜成像及应用
8
、通过构建知识框架和网络，使学生牢记基础知识，掌握分析问题的方法。<
/p>
。
9
、通过习
题的练习，掌握光现象的相关知识。
【呈现形式】
常以填空题、选择题、作图题、实验题的形式出现，例如：对反射
定律以及
折射定律的实验验证可以通过实验题的形式进行考查。对反射（折射）
现象和反射
（折射）
光路可以通过作图题进行考查。
平面
镜的成像的特点可以通
过实验或选择题的形式进行考查。透镜的应用通过填空或选择题德
形式考查。
【授课形式】
实验教学；
实例教学；识记教学；例题教学；教材展示教学等
【知识结构】
一、光的产生：光源
二、光的直线传播
1
．条件：在均匀介质中沿直线传播
2
．现象：
（
1
）小孔成像；
（
2
< br>）影子的形成；
（
3
）日、月食
的形成；
（
4
）三
点一线。
3
．真空中的光速：<
/p>
c
＝
3
×
10
8
m/s
三、光的反射
1
、
光的反射定律：
反射光线与入射光线和法线在同一平面内
；
反射光线和
入射光线分居法线两侧；反射角等于入射角。即“
三线共面，两角相等，法线居
中。
”
2
、光的反射类型：
（
1
）镜面反射（照镜子）
；
（
2
）漫反射（看黑板；物体
的颜色）<
/p>
。
3
、平面镜
成像特点：
（
1
）平面镜所成的像为虚
像；
（
2
）像和物到镜面的距
离相等（
3
）像和物体的大小相等；
（
4
）像与物体相对平面镜对称
< br>
四、光的折射
1
、折射定律：折射光线与入射光线和法线在同一平面内。折射光线与入射光线
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for the
分居法线两侧
。
当光从空气斜射入其他介质中时，
折射角小于入射角；
当光从其
他介质中斜射入空气时，
折射角大于
入射角。
当入射角增大时，
折射角也随着增
大。当光线垂直射向介质表面时，传播方向不改变。
2<
/p>
、现实现象的解释：海市蜃楼；筷子弯了等
五、光的色散
（
1
）白光由红、橙、黄、绿、蓝、靛、紫七色光组成。
<
/p>
（
2
）光的三基色：红、绿、蓝；
颜料的三基色：红、黄、蓝；
（
3
）物体的颜色
六、透镜及其应用
1
、凸透镜：
（
1
）凸透镜的主
轴、焦点、焦距；
（
2
）凸透镜对光线
的作用；
（
3
）
凸透镜的成像特点
2
、凸透镜成像：
物体在一倍焦距内，
呈正立放大的虚像；
放大镜
在一倍焦距和二倍焦距之间，
呈倒立放大的实像；
幻灯机
在二倍焦距之外，
呈倒立缩小的实像。
照相机
3
、
凹透镜：
（
1
）凹透镜对光线的作用；
（
2
）凹透镜的主轴、焦点、焦距；<
/p>
（
3
）
近视眼的
矫正。
【真题大练兵】
（
2011
年）
在图
1
所示的四个情景中，属于光的直线传播形成
的是
丹顶鹤在水中的倒影
射灯射出的光柱
铅笔在水面处“折断”
雨后的彩虹
A
B
C
D
图
l
（
20
11
年）
将远处物体成像在视网膜之前的是
_______
眼，应佩戴
_______
透镜
制成的眼镜矫正。
（<
/p>
2011
年）
图
1O
中
0B
是一条反射光线，
ON
为法线。请在图中画出相应的入
射光线。<
/p>
（
2010
年）
2009
年
7
月
22
日，
重庆市民领略了
500
年一遇的日全食天象奇观，
如图
4
所示，
每一个观察者都被这大自然的奇观速所吸引和震撼，
其实日食的产
生是由于光沿
传播形成的。
我们眼球内的晶状体相当于
镜，
能会聚
光线。
（
2010
年）
同学们在中考考室力，能从不同方向考到监考老师在黑板上所写的
“本堂考室科目：<
/p>
XX
、
考室时间：
XX
”
等提示语，
这是因为光发生了
反
射的缘故。
把一支铅笔斜插入盛水的玻璃杯里，
看上去铅笔好像在水面上折断了，
入股
6
< br>所示，这种现象是由于光的
现象引起的。
（
2010
年）
在如图所示的光学仪器中，使用时主要利用反
射成像的是（
）
（
2009
年）
改革开放
30
年来，我国人民的生
活水平得到迅速提高，照相机、
摄像机已经进入了普通家庭
,<
/p>
它们的镜头相当于一个
透镜，拍摄时所成的像
是倒立缩小的
(
选填“虚”
、
“实”
)
像。
（
2008
年）
一束激光在空气中传播
2
秒钟，通过的路程约为
___________m
；当
这束激光以<
/p>
30
度的入射角射到平面镜上时，反射角是
____________
度。
compa
ny's
economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for
the
第三章
物态变化
【考点聚焦】
1.
温度和温度计的使用。
2
．物质三态间相互转化及吸热、放热的情况。
3
．晶体的熔点
,
并会查熔点表。
4
．液体的蒸发和影响蒸发快慢的因素。<
/p>
5
．液体的沸腾和沸点与压强的关系。
6
．应用物态变化知识解释简单的热现象。
7
、通过构建知识框架和网络，使学生牢记基础知识，掌
握分析问题的方法。
。
8
、通过习题的练习，掌握物质三态间相互转化的关系。
【呈现形式】
解释生产和生活中物态
变化的实例
,
固体、液体、气体是物质存在的三种状
态。
由某种物态变化的现象判断属于何种变化并且判断物态变化中的吸放热
情况，
温度计的使用，
物态变化的图像是中考试命题的重点。<
/p>
常以填空题、
选择题和实
验题形式出现。
【授课形式】
实验教学；实例教学；
识记教学；例题教学；教材展示教学等
【知识结构】
温度
1
．温度的意义
2
．摄氏温度与热力学温度
3
．温度计：
（
1
）液体温度计的原理；
（
2
）正确使用温度计。
(3)
会读温度计的读
数（实验题经常出现）
二、物态变化
1
．熔化和凝固：
熔化：固态
→
液态（吸热）
凝固：液态
→
固态（放热）
（
1
）晶体和非晶体熔化，凝固条件；
（
2
）晶体和非晶体熔化，凝固特点。
2
．汽化和液化：
（
1
）汽化：液态
→
气态（吸热）
（
a
）蒸发：蒸发的特点及条件；影响蒸发快慢的因素。
<
/p>
（
b
）沸腾：沸腾的特点及条件；沸点与
压强的关系。
（
2
< br>）液化：气态
→液态（放热）
3
．升华和凝华
升华：固态
→
气态（吸热）
凝华：气态
→
固态（放热）
【友情提示】
熟记六种物态变化的名
称：熔化、汽化、液化、凝固、升华、凝华。
2
．温度计的正确使用：
（
1
）
“一看二清”
。观察它的量程；认清它的分度值。
（<
/p>
2
）
“三要”
。
（
a
）温度计的玻璃泡要全部浸入被测
液体中，不能碰到容器壁或
底；
（
b<
/p>
）温度计的玻璃泡浸入液体后要稍候一会儿，待示数稳定后再读数；
（
c
）
读数时玻璃泡要继续留在被测
液体中，视线与液柱的上表面相平。
3
．运用熔化和凝固的条件和特点以及图像判断物态变化和吸放热过程。
液化
（雾；露珠）
汽化
（夏天，衣服变干；
）
凝固
（冰）
熔化
（冰融化）
凝华
（霜；窗子上的冰花）
升华
（冬天，衣服边干；樟脑球变小）
【
真题大练兵】
（
2011
年）
4
．下列现象与物理知识相对应的是
A
．深秋早晨的雾——液化
B
．磁铁能吸引大头针——分子间存在引力
<
/p>
C
．灰尘在空中飞舞——分子在永不停息地运动
< br>
D
．冬季人们常用热水袋取暖——做功改变物体内能<
/p>
（
2011
年
）
10
．探究“水的沸腾
的实验中，水在沸腾时需要
______
热量，温度
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for
the
________
。
（
2010
年）
近年来
，美丽山城天更蓝、水更清，大雾天气明显比往年少……。
2010
年
2
月，重庆市被命名为“国家园林城市”
。其中雾的形成属于物态变化中
的（
）
A
．熔化
B
、液化
C
、汽化
D
、升华
（
2010
年）
同学们在理发店洗头时，常会看到理发师用电吹风
给顾客吹头发的
情景，如图
9
所示。请
你从此情景中找出一个与力、热或电有关的物理现象，并
指出与该物理现象对应的物理知
识（不得与示例重复）
。
示例：
物理现象：
< br>电吹风吹出的风使头发飘动起来；
物理知识：
力可以改变
物体的运动
状态。
物理现象：
物理知识：
（
2009
年）
如图
2
所示，描述晶体熔化过程的曲线是
（）
（
2008
年）
2008
年
5
月
27
日
11
时
02
分，
“风云三号”精确预报
气象卫星在太
原卫星发射中心升空，
这颗世界上最先进的对地观
测卫星将在抗震救灾和北京奥
运会期间发生重要作用。
图
9
是运载火箭携带卫星发射升空的情景。
在火
箭点火
时，只见火箭底部的水池中涌出大量的“白气”
，火箭和
卫星就逐渐加速向上腾
空而起，场面蔚为壮观。
(1)
这些“白气”实质上是水蒸气
_________
而成的（填物态变化名称）
，水蒸
气在发生这一变化
的过程中需要
________
热量（填“吸收”
、
“放出”
）
。
(2)
根据这个过程中的现象，请参照下面的示例，说出两个与能量相关的物理
知识。
示例：火箭点火时，燃料的化学能转化为内能。
1
_________________________________
_____________
。
○
2
_______________
_______________________________
。
○
第四章
电流和电路
【教学目标】
1.
知道两种电荷及其相互作用规律。
2.
知道电路各组成部分的基本作用。
3.
串联电路中电流的特点。
4.
并联电路中电流的特点。
5.
电流的概念：形成、方向、效应。
6.
测量电流：会用电流表测电路中电流。
7.
电压及电压表的正确使用
8.
通过构建知识框架和网络，使学
生牢记基础知识，掌握分析问题的方法。
9.
通过习题的练习，掌握电路串并
联特点以及电压表、电流表的使用。
【呈现形式】
由电路情况判断电路中
出现了何种错误并且会改正电路错误，
电流表以及电压表
的使用
，
电学是中考试命题的重点。
常以填空题、
选择题和实验题以及计算题的
形式出现。
【授课形式】
实验教学；实例教学；识记教学；例题教学；教材展示教学等
【知识结构】
1
、
摩擦起电
(
教材展示
)
正电荷：用丝绸摩擦过的玻璃棒上所带的电
负电荷：用毛皮摩擦过的橡胶棒上所带的电
< br>同种电荷相互排斥、异种电荷相互吸引。扩展：静电感应（教材展示）
2
、
（
1
）电路：用导线把电源、用电器、开关连接起来组成的电流通路称
为电
路。
（实例教学）
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for the
定义：能够提供持续电流的装置（或
把其他形式的能转化为电能）
作用：在电源内部不断聚集正电荷，负
极聚集负电荷，以持续对外供电
电源
化学电池
干电池
电路组成
蓄电池
种类
光电池
发电机
用电器：消耗电能
开关：控制电路通断
导线：输送电能
通路：
处处连通的电路
（
2
）电路
开路：
在某处断开的电路
短路：
电源两极不经过电器直接连通
的电路
（
3
）电路图：用规定的符号表
示电源、开关、用电器等电路元件，并表示电
路连接情况的图。
（教材展示、识记教学、实例教学、例题教学）
加油站：
电池有正负两个极。
在电路中，
电池的正极
用
“
+
”
表示
，
负极用
“
-
”
表示。电流是电荷的定向移动，物理学上规定，正电荷定向移动的方向为电
流的方向。根据这个规定，电流接通时，电流总是从电源的正极流出，经过
导线、用电器等流入电源的负极。
3
、电流及其测量：
电流的形成：电荷的定向移动
电流的
方向：正电荷的定向移动方向，在电源外部电流从正极流向负极。
q
电流的大小：
I
t
电荷的多少叫电荷量，
用符号
Q
表示，
国际单位中，
电荷量
Q
的单位是库仑，
简称库，符号是
C
电流表的使用：
电流表与被测电器串联，不允许将
电流表与用电器并联
(
否则短路，烧毁
电流表。
电流要从
接线柱入
,
从
接线柱出
(
否则指针反转
,
容易把针打弯。
被测电流不要超过电流表的量
程
(
可以采用试触的方法来看是否超过量程。
< br>
绝对不允许不经过用电器而把电流表连到电源的两极上
(
电流
表内阻很小，
相当于一根导线。若将电流表连到电源的两极上，轻则指针打歪，重则
烧坏电流表、电源、导线。
使用步骤：
A.
校零，用平口改锥调整校零按钮。
B.
选用量程（用经验估计或采用试触法）
读数
a)
看清量程
b)
.
看清分度值
(
一般而言
,
量程
0~3A
分度值
为
0.1A,0~0.6A
为
0.02
A)
c)
.
看清表针停留位置
(
一定从正面观察
)
3
、电压及其测量：
电压是使导体中的电荷定向移动的原因；
常见电压值：一节干电池：
1
、
5
V
；一节铅蓄电池：
2V
；家用电路：
220V
电压表的使用：
电压表与被测电器并联，要测哪部
分电路的电压，电压表就和那部分电
路并联。
电压表接进电路时，应使电流从<
/p>
接线柱入，从
接
线柱出（否则指针
反转，容易把针打弯）。
被测电压不要超过电压表的量程<
/p>
(
可以采用试触的方法来看是否超过量程。
电流表、电压表对比：
符号
与被测对象的连接方式
能否直接连接电源
异
量
程
每大格
每小格
内阻
同
电流表
串联
不能
0.6A
和
3A
0.2A
和
1A
0.02A
和
0.1A
很小，几乎为零
相当于短路
电压表
并联
能
3V
和
15V
1V
和
5V
0.1V
和
0.5V
很大，相当于断路
使用前要调零；读
数时看清量程和每大（小）格；正接线柱流入，负接线
柱流出；所测量的值不能超过自身
量程。
4
、串、并联电路中的电流、电压特点
串联：
电流处处相等，即
I=I
1
=I
2
=
……
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for the
电路两端总电压等于各部分电路两
端的电压之和，即
U=U
1
+U
2
+
……
并联：干路电流等于各支路电流之和，即
I=I
1
+I
2
+
……
各支路两端的电压相等，即
U=U
1
=U
2
=
……
定义
串联
把元件逐个顺次连接起
来的电路
特征
电路中只有一条电流路
电路中的电流路径至少有两条，各支路中的
径，各元件不能独立工
元件独立工作，互不影响。
作，相互影响。
开关
控制整个电路
作用
电路图
干路中
的开关控制整个电路。支路中的开关
控制该支路。
并联
把元件并列的连接起来的电路
电流特
点
电压特
点
I
=
I
1
＝
I
2
U
＝
U
1
＋
U
2
< br>I
＝
I
1
＋
I
2
U
＝
U
1
＝
U
2
【真题大练兵】
选择题：
(2011
年
)
5
．在图
3
所示的电路中，闭合开关后两盏灯
都可能发光的是
A
．只闭合开关
S
1
B
．只闭合开关
S
2
<
/p>
C
．只闭合开关
S
1
、
S
2
D
．开关
S
1
、
S
2
、
S
3
都闭合
图
3
6
．某
导体中的电流与它两端电压的关系如图
4
所示，下列分析正确的
是
A
．当导体两端的电压为
0
时，电阻为
0
B
．该导体的电阻随电压的增大而减小
C
．当导体两端的电压为
0
时，电流为
0
D
．当导体两端的电压为
2
V
时，电流为
0.6A
图
4
（
20
10
年）
重庆市高速公路收费站于去年开始对过往的超载货车实
施计重收费，
某同学结合所学物理知识设计了如图
3
所示的计重秤原理图，
以下说法正确的是
（
）
A
、称重表相当于一个电压表
B
、电路中的
R
1
是没有作用的
C
、当车辆越重时，称重表的示数越小
D
、
当车辆越重时，称重表的示数越大
（
2009
年）
如图
3
所示的四种情景中，符合安全用电原则的是
(
)
A
、徒手从输电线上取风筝
B
．电灯的开关必须接在零线上
c
．家庭电路中导线绝缘层破损
．
D
、三脚
插头的“长脚”与用电器的金属外壳相连
（
< br>2009
年）
李明同学为了探究“电功率与电阻的关系”
，他找来额定电压均为
6v
的
L1
、
L2
两只灯泡。
将两灯串联起来，
按照图
5
所示的电路开始了实验探究，
闭合开关后，看见灯
L2
微微发光，灯
L1
几乎不发光，则
关于两灯的电阻
R1
，
和
R2
、两灯的额定功率
P1
和
P2
的大小关系成立的是
(
不
考虑灯丝电阻值随温
度的变化
)
(
)
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for the
A
、
R1>R2
P1>P2
B
．
2008 所示的电路中，电源电压为 <
br>_______A
2011
内转 <
br>、 3 、℃） 、知道什么是电阻，知道电阻的大小与哪三个因素有关。 <
br>、掌握伏安法测电阻的原理及电路图，学会如何排除电路故障 <
br>08 <
br>10 、通过习题的练习，掌握欧姆定律的计算和伏安法测电阻实验。
、电阻：导体对电流的阻碍作用（符号，单位） U <
br>
<
br>,
…
并联中，如果是两个电阻并联有 <
br>年）
L _______ 接线
<
br>1 结合表中数
<
br>重复上面的实验时，需要改变
R1
Pl
C
．
R1>R2
P1
D
．
R1
P1>P2
（
年）如图
5
所示，家庭照
明灯的一种按键开关上常有一个指示灯。在实
际使用中发现：当开关闭合时，只有照明灯
发光；开关断开时，照明灯熄灭，指
示灯会发出微弱光，以便夜间显示开关的位置。根据
这种按键开关的控制特性，
能正确表示照明灯（甲）和指示灯（乙）连接方式的电路图是
图
6
中的
（）
指
示
图
填空题：
（
2011
年）
8
．
教室里的电风扇与日光
风扇正常工作时电压为
_______V
。
（
2011
年）
12
．在图
6
3 V
。闭合开关
S
，电流表①
的示数为
1.
2 A
，电流表②的示数为
0.3A
，
则通过
R
1
的电流是
，
R
2
的阻
值是
_________
Ω
。
（
年）
13
．小明家中的电
能表如图
7
所示，从表盘信息可知，小明家接入
的用电器总功率不能超过
_________W
。当家
里只有微波炉工作时，电能表在
1
min
60
转，则微波炉消耗的电能为
___________J
。
图
6
灯是
_
________
联，电
图
6
图
7
（<
/p>
2010
年）
某品牌快速电热水壶，其铭
牌上标有“
220V
1500W
”<
/p>
。在标准大气
压下，将质量为
1
、
5kg
，温度为<
/p>
40
℃的水烧开，水需要吸收的热量是
J
。
若不计热损失，电热水壶正常工作时烧
开这壶水的时间是
S
。
（水的比热容为
4
2
×
10
J/
（
kg
）
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for
the
第五章
电阻及欧姆定律
【教学目标】
1
2
、知道滑动变阻器的原理，会正确使用滑动变阻器。
3
、熟练掌握欧姆定律的表达式及其物理意义，会用欧姆定律进行简单
计算。
4
、通过习题的练习，掌握串
联和并联电路电流、电压、电阻的关系。
5
（
、
09
、
年
中考实验中均有涉及）
。
6
、电阻的串联和并联
7
、了解家庭电路和安全用电知识
<
/p>
8
、通过构建知识框架和网络，使学生牢记基础知识，掌握分析问
题的方法。
。
9
【呈现形式】
串并联电路电流、电压
、电阻的关系，滑动变阻器的正确使用，欧姆定律以及由
欧姆定律延伸出来的伏安法测定
值是中考试命题的重点。
常以填空题、
选择题和
实验题以及计算题的形式出现。
【授课形式】
实验教学；实例教学；识记教学；例题教学；教材展示教学等
【知识结构】
1
材料
电阻的影响因素
长度：长度越长，电阻越大
（实验探究）
横截面积：横截面积越
小，电阻越大
滑动变阻器：原理通过改变导线的长度来改变电阻
2
、变阻器
接法：一上一下
电阻箱
3
、
（
1
）实验探究：电流的影响因素
得出结论：保持电阻不变时，电流跟电压成正比关系
保持电压不变时，电流跟电阻成反比关系
（
2
）欧姆定律：
I
（结合电流、电压特点解题）
R
加油站：
由欧姆定律知
:
否正确？
4
、
“伏安法”测电阻
（结构示意图）
那么知，电阻与电压成正比，与电流成反比，是
原理：欧姆定律的变形公式
通过例
题熟悉“伏安法”测电阻的电路图、试验故障等相关考试重点。
5
、电阻的串联和并联（串联分压和并联分流原理）
串联：由
U
总＝
U1
+U2+
……，
I
总＝
I1
＝
I2
＝
I3
＝……
则，
R
总＝
U
总
/I
总＝
R1+R2+R3+
……
并
联
：
U
总
＝<
/p>
U1
＝
U2
＝<
/p>
…
…
，
I
总
＝
I1+I2+I3+
…
则
，
U
总
/R
总
=U1/R1+U2/R2+U3/R3+
……
由
并联：
U
总＝
U1
＝
U2
＝……约掉所有的
U
，
所以
1/R
总＝
1/R1+1/R2+1/R3+
……
R
总
=(R1+R2)/R1R2
6
、家庭用电
进户线：连接户外的供电电路的电线，通常有两根，一根火线，一根零线。火线
和零线
之间的电压是
220V
。
地线不与外边进户线相接，而是连接在住宅楼埋入大地的接地导体上。
家庭电路中的三孔插孔中的一个孔就是连接在底线上的。
人体安全电压是不高于
36V
。
【真题大练兵】
<
/p>
（
2009
年）
学习了电学知识以后，好学的李明仔细观察了家中电热水壶
的
铭牌
(
如右表
)
，电热水壶正常工作时的功率为
W
他将电
热水壶中装满水，通电
1
．
5min<
/p>
后，测出水温从由
20
℃上升到
40
℃。
在此过程中，水吸收热量
J[c
水
=4
、<
/p>
2
×
10
3
J/kg
、℃
]
实验题：
（
2011
l8
．小雷想知道小灯的亮暗程度与什么因素有关。
于是找来
额定电流均小于
0.6
A<
/p>
，额定电压是
2.5V
的灯
L
1
和额定电压是
3.8V
的灯
L
2
，先
后接在电源电压恒为
6V
的电路中，按
照如图
l6
所示的电路开始探究。
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for the
图
16
图
17
(1)
请你用笔画线代替导线，根据图
16
所示的电路图，将图
17
所示实物
图连接
完整。
(2)
若小雷连接
Eg
路后闭合开关，灯
1
几乎不发光，移动滑片
P
也不能改变灯的
亮度。原因是他把滑动变阻器的
、
_______
．
(
选填“
AB
”或“
CD
”
)
柱接入了电路。
(3)
小雷排除故障后，按图
17
所示的电路继续
进行实验：
①闭合开关，滑片
P
向
_______(
选填“
A
或“
B
端移动，使灯
L
1
发光，测出灯
L
1
的相关物理量，记录和计算结果如下表：
实际功率／
次数
电压／
V
电阻
Ω
W
1
2
3
②请将记录数据时遗漏的物理量和单位填入表格的空格处。
<
/p>
(4)
小雷注意到灯
L
的亮度变化是：第二次比第一次亮，第三次比第二次更亮。
据得出的结论是小
灯泡越亮，它的实际功率越
________
。
(5)
用
L
2
替换
L
1
_______
表的量程，
发现灯
L
2
的亮
度变化规律与灯
L
1
相似。
(6)
小雷在实验结束后与同学们讨论：
①有同学认为“用上表中灯
L
1
的
3
次电阻的平均值代
表它的电阻更准确。
这种
说法错
误的原因是小雷忽略了
__________
．对
小灯电阻的影响。
②有同学认为“把灯
L
1
换成定值电阻，该实验可以用来研究导体中的电流与电<
/p>
压的关
系。
你认为
这种说法
___________(
选填“正确”或“错误”<
/p>
)
。
（
2010
年）
楠楠同学在资料上看到了一份材
料，某大学物理系的同学再测定额
定电压为
2
< br>、
5V
小灯泡的电阻的实验中，得到部分
U
和
I
的数据如下表所示：<
/p>
实验次数
1
2
3
4
5
6
1
．
6
2
．
5
2
．
8
O
．
20
O
．
24
O
．
26
O
．
32
O
．
60
O
．
73
8
．
00
1O.42
1O
．
77
U/V
I/A
0
、
20
0
、
02
0
、
80
0
、
08
1
、
40
0
、
14
2
、
00
0
、
18
2
、
50
0
、
20
3
、
00
0
、
21
（
1
）楠楠根据表中的数据，画出该小灯泡的电流跟电压变化的图
像，于是设计
了如图
17
所示的坐标图
。
①请你帮楠楠在坐标图中画出该小灯泡的电流跟电压变化的
图像；
②从材料或图像中可知，该小灯泡的额定电流为
A
，正常发光时的电阻为
Ω
；
（
2
）楠楠还想利用初中的物理实验器材，通过实验来验证上述表格中
的每一组
数据是否正确，于是她又设计了入股
18
甲所示的电路图，同时找来了实验器材
并连接了部分实物电路，
其中电源用的是
2
节新干电池，
滑动变阻器的电阻可在
0~50
Ω
内调节。
请你用笔画线代替导线，
按照图
18
所示电路图，
帮楠楠将图
18
乙中的实物电路
图连接完整；
闭合开关前，滑动变阻器的滑片应移到
端（选填“
A
或
B
”
）
；实验中，
compa
ny's
economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for the
由于操作不小
心等原因，
导致电压表的示数变为零，
电流表的示数增大，
则电路
可能出现的故障是
。
楠楠通
过这个实验来验证上述表格中的每一组实验数据的正确性，
你认为楠楠能
做到吗？请简要说明理由。
。
（
200
9
）
在“测定小灯泡的额定功率”实验中，张超同学用一个电压
表、一个
电流表、二个开关、电压为
6V
的电源、额定电压为
3
．
8 V
的小灯泡和一个标有
“
20
Ω
,1
．
5A
”
的滑动变阻器，设计了如图
14
甲所示的电路。
(1)
如果小灯泡的额定功率小于
2w
，电流表的量程选
A
为宜；
(
2)
请用铅笔画线代替导线，按照图甲所示的电路图，将图乙的实物电路连接完
整
(
连线不得交叉
)<
/p>
；
(3)<
/p>
在实验中，
若电压表示数为
2
V
，
则灯泡的实际功率
额定功率
(
选填
“
>
”
、
“
<
”或“
=
”
)
；
(4)
当滑动变阻器的滑片向左移动时，电流表示数增大，则变阻器接人
电路的接
线柱应是和
。当电压表的示数为
V
时小灯泡正常发光，此时电流
表示数为
0
、
4A
，则灯泡的额定功率为
W
；
(5)
另一组的同学按同一电路连接好最后一根导线，灯泡立即发出明亮耀眼的光
并很快熄灭。检查后发现连线正确，请你找出实验中两个操作不当之处：
1
○
②
（
2008
年）
（
10
分）
实验桌上准备的器材如图
12
所示：
一个电池组
（电压稳定）
、
一个电流表、一个电压表、一个滑动变阻器
、一个开关、导线若干。小明想利用
这些器材测定某待测电阻
R
X
的阻值。
（
1
）
请你用笔画线帮助小明将实物图连接完整，
并在右边的虚框中画出对应
的电路图（
5
分）
。
（
2
）小明按照要求连好电路后，闭合开关前，变阻器的滑片应置于<
/p>
_______
端（选填“左”或“右”
）
，这样做的目的是为了
________________<
/p>
。
（
2
分）
（
3
）
闭合开关后，<
/p>
发现电流表指针有明显偏转。
若电压表指针未动或几乎未动，
请你
分析产生这类现象的原因有哪些？（
3
分）
例如：电压表已损坏。
1
____________________________________________
。
○
2
__________________________
__________________
。
○
3
____________________________________________
。
○
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for
the
第六章
电功率
【教学目标】
1
、知道电流做功与那些因素有关
2
、知道电功的定义和计算方法
3
、知道电功率的定义、计算公式以及测定电功率的实验方法
4
、通过构建知识框架和网络，使学生牢记
基础知识，掌握分析问题的方法。
。
5
、通过习题的练习，掌握电功和电功率的计算。
【呈现形式】
电功以及电功率的定义
、物理意义、计算是中考试命题的重点。常以填空题、选
择题和实验题以及计算题的形式
出现。
【授课形式】
实验教学；实例
教学；识记教学；例题教学；教材展示教学等
【知识结构】
多少功，用电器就消耗
了多少电能，也就有
电功的意义：电
流做了
式的能。
< br>多少电能转化为其它形
电功的大小：
< br>W
＝
UIt
。
< br>
焦，符号
J
。
国际单位为焦耳，简称
电
功的单位
6
实用单位为千瓦时，用
符号
kW
<
/p>
h
表示，
1kW
h
＝
3.6
10
J
能表。
1
、
电功
测量电功的仪器－－电
导体具有电阻，所以当
有电流通过
电流的热效应－－由于
时，导体会发热，将电
能转化
为内能。
电功与电热
）：
Q
＝
I
2
Rt
。
< br>
电热的大小（焦耳定律
<
/p>
热；
在电热
器中，电功＝电
电功与电热的关系
电热。
在其他电路中，电功＞
流做功快慢的物理量。
电功率的意义：表示电
电功率的大小：
P
＝
UI
2
、电功率
电功率的单位：国际单
位为瓦特，简称瓦，符
号为
W
，
1W
＝
1J/s
。
W
电功率与电功的联系：
P
＝
。
t
【真题大练兵】
计算题：
（
2011
年）
20.<
/p>
从
2011
年
5
月
11
日起，执行酒驾重罚新规定。交
警使
用的某型号酒精测试仪的工作原理相当于图
19
所示。
电源电压恒为
9 V
，
传感器
电阻
R
2
的电阻值随酒精气体浓度的增大而减小，当酒精气体的浓度为
0
时，
R
2
的电阻为
80
Ω
。使用前要通过调
零旋钮
(
即滑动变阻器
R
1
的滑片
)
对测试仪进行<
/p>
调零，此时电压表的示数为
8
V
。求：
(1)
电压表的示数为
8V
时，电流表的示数为多少
?
(2)
电压表的示数为
8V
时，滑动变阻器
R
1
的电阻值为多少
?
(3)
调零后，
R
1
的电阻保持不变。
某驾驶员对着测试仪吹气
10 s
，
若电流表的示数
达到
0.3A
< br>，表明驾驶员醉驾，此时电压表的示数为多少
?
图
19
(2010
年
)
有的小汽车前排座位中安装有高低档的电加热，
其工作原理相当于如
图
19
所示的电路图，
其中<
/p>
R
1
=12
Ω<
/p>
，
R
2
=6
Ω
，
闭合开关后，
通过
R
1
的电流为
2A
，
求：
（
1
）
R
1
两端的电压；
（
< br>2
）通过
R
2
< br>的电流。
（
2009
年）爱思考的林刚利用图
16
所示的电路进行实
验，当闭合开关
s
后，发
现标有“
6V , 3 w
”的灯
Ll
和标有”
12v , 3w
”的灯
< br>L2
，亮度并不相同。巳知电源
电压为
< br>6V
，不考虑灯丝电阻值随温度的变化。求：
(1)
通过灯泡
I1
的电流为多大
?
(2)
灯袍
Ll
每分钟消耗多少电能
?
(3)
灯泡
L2
的实际功率是多大，电路中灯
L1
、和
L2
哪个更亮
?
（
2008
年）
（
8
分）物理实验室有一个微型电动机，铭牌上标有“
12V3W
”的字
样。兴趣小组的同学想让这个电动机正常工
作，但手边只有一个电压恒为
18V
的电源，于是他们找来一个
阻值合适的电阻
R
与之串联后接入电路（如图
< br>14
所
示）
，使小电动机刚好正
常工作。
求：
（<
/p>
1
）小电动机正常工作时的电流；
（
2
）整个电路在
1
分钟的时间内消耗的总电能；
（
3
）小电
动机正常工作时，电阻
R
消耗的电功率。
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the
Departme
nt of investigation and
follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for
the
第七章
电与磁
【教学目标】
1
、知道磁场的定义、磁体周围磁感线的分布及磁体间的相互作用。
2
、理解磁场对电流的作用及其应用（安培定则）
。<
/p>
3
．理解电磁感应现象的产生条件。
4
、知道电动机与发电机的原理。
<
/p>
5
、通过构建知识框架和网络，使学生牢记基础知识，掌握分析问
题的方法。
。
6
、通过习题的练习，掌握安培定则和电磁感应现象。
【呈现形式】
安培定则，
电磁感应现象是中考试命题的重点。
常以填空题、
选择题和实验题形
式出现。
【授课形
式】
实验教学；实例教学；识记教学；例题教学；教材展示教学等
【知识结构】
1
、磁体周围的空间存在着磁场。磁场是一种看不到摸不着而又确实存在的一种
特
殊形态的物质。
2
、安培定则，也叫
右手螺旋定则，是表示电流和电流激发磁场的磁感线方向间
关系的定则。
通电直导线中的安培定则
（安培定则一）
：
用右手握住通电直导线，
让大拇指指向电流的方向，
那么四指的指向就是磁感线的环绕方向；
通电螺线管
中的安培
定则（安培定则二）
：用右手握住通电螺线管，使四指弯曲与电流方向
< br>一致，那么大拇指所指的那一端是通电螺线管的
N
极。<
/p>
3
、
闭合电路
的金属导体在磁场中切割磁感线运动时产生电流的现象称为电磁感
应。
< br>
【真题大练兵】
（
2011
年）
15
．<
/p>
(1)
在图
9
中
，标出任意一条磁感线的方向。
（
2010
年）
1820
年，最能接受他人成果的法国看、物理学家安培在听到丹麦物
理学家奥斯特证实
了“电流的磁效应”这个消息后，在进一步的实验中，又发现
了通电螺线管的磁场分布。
现在我们可以确定图
5
中通电螺线管的
N
极在
端
（选填
“
A
或
B
”
）
。
1821<
/p>
年，
英国物理学家法拉第致力于
“磁生电
”
，
历经十年，
终于发现了
现象，根据这一发现，后来又发明了发电机。
（
2009
年）
英国科学家法拉第经十年不懈探索，于
1831
年发现：闭合电路的
一部分导体在磁场
中
做切割
磁
感线运
动
时会产生
电流。
这种现象被
称为
现象，利用这种现象发明了
机，使人类大规模使用电能成为现实。
（
2008
年）
丹麦物理学家奥斯特
首先发现了电流周围存在
__________
；英国物
理学家法拉第首先发现了闭合电路的一部分导体做切割磁感线运动时，
导体中会
产生电流，这种现象被称为
____________
__
现象
compa
ny's economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to
assessment; 2, for
em
ployee
s worki
ng
in thi
s sect
or allocation,
performa
nce eval
uation and
reward (or puni
shme
nt
recomme
ndati
ons)
aut
hority; 3, withi
n the
limits of responsi
bility
accordi
ng to the
system of
ownershi
p of the w
ork of the
a
uthority; 4,
the
rig
ht to confide
ntiality in
the
com
pany
ar
chives; 5, the rig
ht to
the assessment of de
partments; 6,
request
other department
s
withi
n the De
partment
be reasona
ble
coor
dination aut
hority;
7, the right to revie
w of
the fees; 8, urging im
plementation of
the
personnel manageme
nt
system, and corre
sponding
puni
shme
nt for violations of
the
system recommended
by
the aut
hority;
Department:
General Office two
superiors: jobs covered
by
the Ma
nager and the
subordi
nate de
partments:
Direct
or, General
A
ccounti
ng, Treasury,
material a
ccounti
ng,
appraisal, a
sset manager
de
partments job:
re
sponsi
ble for
dev
elopment, audit,
inspe
ction, evaluati
on,
ma
nagement reg
ulations, and
t
he company'
s financial and
material management. Main functi
ons: 1,
common functi
ons, in
charge
of the a
nnual,
quarterly
a
nd monthly work
plan
a
nd re
port, wit
h
regular w
ork, looking for a job gap,
im
prove the
quality
of work; 2,
re
sponsi
ble for the
company's rul
es and
regulati
ons, prov
isions,
arrangeme
nts, notice
s and
other docume
nts of
impleme
ntation i
n this
sect
or; 3,
responsi
ble for the i
nternal
management rule
s of
constr
uction, impl
ementation
and improvement
of work; 4,
i
n c
harge of the
department
s and agencies
post functi
ons, running
processe
s, the
development
of assessment
methods a
nd
a
ssessment
w
ork;
5, responsi
ble for
the
第八章
信息传递
【教学目标】
1
、
知道信息和信息传播活动所经历的五次巨大变革，
了解早
期的信息传播工具；
2
、理解波的有
关概念，知道电磁波的特性，知道光是电磁波，了解电磁波的应
用；
3
、了解现代通信和信息高速公路。
4
、知道波长、频率和波速的关系，了解波在信息传播中的作用
；
5
、知道光是电磁波，知道电磁波
在真空中的传播速度；
6
、通过构建
知识框架和网络，使学生牢记基础知识，掌握分析问题的方法。
。
7
、通过习题的练习，掌握波长、频率和波速的关系。
【呈现形式】
波的概念，电磁波的特征，波长、频率和波速的关系是中考试命题的重点。常以
填空题、
选择题的形式出现。
【授课形式】
实
验教学；实例教学；识记教学；例题教学；教材展示教学等
1
、信息与信息传播：
1)
信息是各种事物发出的有意义的
消息。
消息中包含的内容越多，
信息量越大。
< br>
2)
人类特有的信息有三种：语言、符号和图像。
3)
在人类历史上，信息和信息传播
活动经历了五次巨大的变革，它们是：①语
言的诞生；②文字的诞生；③印刷术的诞生；
④电磁波的应用；⑤计算机技术的
应用。
4)
早期的信息传播工具有很多，比
如：①万里长城上的烽火台；②古代传递官
文的驿马；
5.
③莫尔斯发明的电报机；④贝尔制作的早期电话。
定义：所有的波都是在传播周期性变化的运动形态
振幅
：波源偏离平衡位置的最大距离
周期
：波源振动一次所需要的时间
波
波的性质
频率
：
波源每秒内振动的次数
波长
λ
：波在一个周期内传播的距离
波的传播速度：
＝
λ
，单位是秒
米
电磁波是在空间传播的周期性变化的电磁场
电磁波的传播不要介质。在真空中传播的速度为
＝
电磁波谱
电磁波
传播的形式：从
“文字
声音
图像”
人类传播信息的历史及变化
传播的信息量“由小到大”
传播的距离“由近到远”
传播的速度“由慢到快”
移动通信：移动用户或移动用户与固定用户之间的通信方式
光纤通信：以激光为光源以光导纤维为传输介质进行的通信
代通信的方式
卫星通信：利用人造地球卫星作为中继站，转发无
线电信号，
在多个地球站之间进行的通信
互联网络
电磁波普：
从电磁波谱图可知，电磁波包括了：无线电波、微波、光（包
括红外线、可
见光和紫外线）
、
X
射线和
γ
射线等。
【习题大练兵】
例
1.
下列说法中正确的是：
（
）
A.
频率越高的电磁波，传播速度越大；
B.
波长越短的电磁波，传播速度越大；
C.
频率越高的电磁波，波长越短；
D.
波长不同的电磁波，频率不同，因而速度亦不同。
分析：
电磁波的传播速度与波长和频率无关，
仅由
传播的介质决定，
电磁波
在同一物质中的传播速度是不变的，<
/p>
在真空中的传播速度等于光速，
在空气中的
速度近似等于光速。
但电磁波的波长、
频率及传播速度三者满
足：
传播速度＝波
长×频率，因此电磁波的频率与波长成反比关
系。
compa
ny's
economic
obje
ctives, task
breakdown, implementati
on,
a
ssessment w
ork; 6, the
com
pany responsi
ble for
runni
ng the pr
ogram as a
whole, r
unning pr
ograms
acr
oss
departme
nts of the
implementation, follow-up,
fee
dba
ck,
revisi
on; 7, in charge of the
i
nternal
nt work; 8, is
responsible for
organizi
ng
this
Confere
nce
a
nd trai
ning
wit
hin the Department; 9,
re
sponsi
ble for the
promoti
on
of the
cultural constructi
on
of
enterpri
ses in t
his
sector
; 10 and subordinate
de
partments, i
n
charge of the De
partment's
a
ssets ma
nagement;
11, in
charge
of
the inter
nal statistical
reports submitted
work and
cr
oss examinati
on
ta
ble; 12, responsibl
e for
the se
ctors
covere
d by the
community relations and
busi
ness rel
ations
coordi
natio
n and liaison
w
ork with
superior
counterpart
s; 13, i
s
responsible for t
he special
i
nspecti
ons and
r
outi
ne check
s of
company
organizati
on; 14,
are responsi
ble for the
e
stablishment
of
busi
ness customers ' file;
15, responsible for safety within
t
he juri
sdi
ction
of the Departme
nt of
investigation and follow
-up; 16
rationali
zation a
ctivities,
i
n charge of the
Department'
s work, to
colle
ct, compile
a
nd re
port on a regular
basis, implementati
on;
17, are responsi
ble for the
duction
ngzeng
shua
ngji
e
ctivity; 18, are
responsi
ble for the transfer of the
information to be filed into t
he
work
; 19, is i
n charge of
the De
partment's eval
uation
work
; 20, is
re
sponsi
ble for regular
re
porti
ng on the
pr
ogress
of work in
thi
s se
ctor to higher
a
uthoriti
es; 21, functions
and business are re
sponsi
ble
for the
cust
ody
of the seal,
use
;
22, are responsible for the material
delivery acce
ptance; 23 to