问题
问答题
如图所示,小灯泡L标有“6V 0.3A”字样,R=30Ω,闭合开关S,小灯泡正常发光,则电流表的示数是多少?
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答案
∵L与R并联,且L正常发光,
∴UR=UL=6V,IL=0.3A,
IR=
=UL R
=0.2A,6V 30Ω
电流表的示数为:
I=IL+IR=0.3A+0.2A=0.5A.
答:电流表的示数为0.5A.
如图所示,小灯泡L标有“6V 0.3A”字样,R=30Ω,闭合开关S,小灯泡正常发光,则电流表的示数是多少?
∵L与R并联,且L正常发光,
∴UR=UL=6V,IL=0.3A,
IR=
=UL R
=0.2A,6V 30Ω
电流表的示数为:
I=IL+IR=0.3A+0.2A=0.5A.
答:电流表的示数为0.5A.