本题目来源于试卷: Electricity and Circuits: Resistor，类别为 美国物理杯赛(Physics Bowl)
[单选题]
02.22: An ideal battery, an ideal dahwhv3 ;p s)8 o-**+atmby96tmls yoammeter, a switch and three resistors are connected as shown. With the switch open as shown in +o 9ba tl-*y6most*ym the diagram the ammeter reads 2.0 amperes.
With the switch open, what must be the voltage supplied by the battery?
A. $30 V$
B. $40 V$
C. $60 V$
D. $70 V$
E. $110 V$
参考答案: D
本题详细解析:
暂无
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