初三物理-家庭电路

初三物理-家庭电路 [知识要点]: 1(如下右图可知道:家庭电路由 、 、 、 、______等组成 2(进户线有两根电线，一根叫 ，另一根叫 ，火线与零线之间有 V的电压。区别火线零线用 笔，使用测电笔时应用手接触 ， 接触电线。如果 ，表示接触的是火线，否则就是零线。 3(电能表的作用是测出用户全部电器消耗的 。 4.如图所示，室内照明电路中，安装错误的地方是_______，如果这样安装将造成_______. 5(造成家庭电路电流过大的原因是 、 。 6(当电路中电流增大到超过线路设计的允许值前，保险丝能 电路起到保护作用。保险丝的材料应选择熔点较 (填“高”或“低”)的铅锑合金。 7(开关与用电器是 连，开关要接在 和 之间。 8(家庭电路的计算一般是用 公式来计算。对人体的安全电压是 。一度电等于 KW•h又等于 J 9.人体触电是指 ，具体讲家庭电路触电有两种情况:一是 ;二是 。 10.安全用电有“四不”，这“四不”是 指 、 、 、 。 [典型例题] 1、在家庭电路中，进户线进入家庭内经过的电器元件的正确排列顺序是: ( ) A、总开关、熔断器、电能表、用电器; B、电能表、总开关、熔断器、用电器; C、电能表、总开关、用电器;熔断器;D、用电器、电能表、总开关、熔断器. consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded specification for construction and acceptance of oil tank 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 HG20201-2000 construction installation engineering construction standard 7, HG ... Pressure gauges, using an installed spark arrestor for acetylene cylinders, illegal carrying, using gas cylinders, each operator fined 20 Yuan. Gas bottle without the hot sun exposure measures, responsibilities of team a fine of 50 Yuan. (7) at height and the opening and provisional protective measures have been taken, the responsible unit fined 200 Yuan, construction 2、原来室内电灯正常发光，在台灯开关断开的情况下，当把台灯的插头插入插 座时，室内电灯全部熄灭，保险丝熔断，发生这一现象的原因可能是: ( ) A、台灯的功率过大; B、插座处原来有短路; C、台灯灯座处有短路; D、台灯插头处有短路. 3.图的四幅图中，符合安全用电原则的是( ) A B C D 4、在图的各种情况下，人体不会造成触电的是: ( ) 3、某家庭电路接线如图1所示，其中接错的元件:( ) A、只有开关S;B、插座H和开关S;C、插座H和开关S;D、只有插座H. 222121 图1 图2 4、如图2所示，合上开关S，发现灯L不亮，用测电笔测试A、B、C、D各点， 只在A点氖管发光，则故障是:( ) D、开关S接触不良. A、BC之间断路; B、灯L断路; C、灯L短路; 5、图3给出了家庭电路中常见的螺丝口灯泡和拉线开关，要求开关控制灯泡， 则A、B、C、D四个电灯的连接中符合连接要求的是: ( ) consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded specification for construction and acceptance of oil tank 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 HG20201-2000 construction installation engineering construction standard 7, HG ... Pressure gauges, using an installed spark arrestor for acetylene cylinders, illegal carrying, using gas cylinders, each operator fined 20 Yuan. Gas bottle without the hot sun exposure measures, responsibilities of team a fine of 50 Yuan. (7) at height and the opening and provisional protective measures have been taken, the responsible unit fined 200 Yuan, construction 6、作图题 (1)、在图4的家庭电路中A、B两处装上最合适的元件(用符号表示). (2)、将图5中的电路元件连接好，使它们符合用电要求。 7、将一台“220 V、1500 W”的电热水器接到220 V的照明电路中，计算: (1)该热水器的电阻多大,热水器在1 min内产生的热量是多少J,工作1 h要用电多少度, (2)如果将接这个电热水器的插座安装保险丝(参照下表的熔丝规格)，应该选取多大直径, 直 径(mm) 0.71 0.81 0.98 1.02 1.25 1.51 额定电流(A) 3 3.75 5 6 7.5 10 熔断电流(A) 6 7.5 10 12 15 20 [拓展训练] 1、如图所示，关于测电笔的使用方法中正确的是 ( ) A B C D 2、小明同学学完家庭电路知识后，安装了某房间的照明电路，如图所示，经检查发现有三处错误，它们是___________、_____________、_____________. consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded specification for construction and acceptance of oil tank 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 HG20201-2000 construction installation engineering construction standard 7, HG ... Pressure gauges, using an installed spark arrestor for acetylene cylinders, illegal carrying, using gas cylinders, each operator fined 20 Yuan. Gas bottle without the hot sun exposure measures, responsibilities of team a fine of 50 Yuan. (7) at height and the opening and provisional protective measures have been taken, the responsible unit fined 200 Yuan, construction 3、白炽电灯是人们常用的照明用具，如图所示. 根据你对白炽灯的了解，请提出两个与物理知识有关的问题，并针对提出的问题作出简要的回答. 例如:问题:白炽灯的灯丝用久了为什么会变细, 简答:在高温状态下工作灯丝升华造成的. 问题:______________________________， 简答:____________________________________________; 问题:______________________________， 简答:____________________________________________; 图 consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded specification for construction and acceptance of oil tank 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 HG20201-2000 construction installation engineering construction standard 7, HG ... Pressure gauges, using an installed spark arrestor for acetylene cylinders, illegal carrying, using gas cylinders, each operator fined 20 Yuan. Gas bottle without the hot sun exposure measures, responsibilities of team a fine of 50 Yuan. (7) at height and the opening and provisional protective measures have been taken, the responsible unit fined 200 Yuan, construction 东城: 如图27所示电路，设电源电压不变。当只闭合开关S时，电流表的示1数是I;当只闭合开关S时，电流表的示数是I;已知I:I=2:1。当通 21212过控制开关S和S，使电路消耗的最大功率和最小功率分别为P和P2总总1 ,，已知电路消耗的总功率达到最小时，电压表V、V的示数之比为2:1，12电阻R消耗的电功率P,为2W，求: 22 (1)电阻R与R之比; 12 (2)电路消耗的最大功率P; 总 (3)在2s内电路消耗的总功率分别达到最小和最大时，产生的热量 Q,与Q之比。 总总V 1 R 3V S1 S 2R R 12 V 2 V 图27 consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded specification for construction and acceptance of oil tank 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 HG20201-2000 construction installation engineering construction standard 7, HG ... Pressure gauges, using an installed spark arrestor for acetylene cylinders, illegal carrying, using gas cylinders, each operator fined 20 Yuan. Gas bottle without the hot sun exposure measures, responsibilities of team a fine of 50 Yuan. (7) at height and the opening and provisional protective measures have been taken, the responsible unit fined 200 Yuan, construction 西城: consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel welding procedures of steel pressure vessel NDT 9 JB/T4744-2000 steel pressure vessel products mechanical properties test of welded plate II, mechanical equipment installation engineering 1 GB150-98 2 GB50128-2005 vertical cylindrical steel pressure vessel steel welded specification for construction and acceptance of oil tank 3 JB/ T4735-1997 steel welded atmospheric pressure vessel 4 GB50231-2009 mechanical equipment installation engineering construction and acceptance specification for 5 GB50275-98 compressor, fan and pump installation engineering construction and acceptance specification for lifting 6 HG20201-2000 construction installation engineering construction standard 7, HG ... Pressure gauges, using an installed spark arrestor for acetylene cylinders, illegal carrying, using gas cylinders, each operator fined 20 Yuan. Gas bottle without the hot sun exposure measures, responsibilities of team a fine of 50 Yuan. (7) at height and the opening and provisional protective measures have been taken, the responsible unit fined 200 Yuan, construction