Question

three resistors each having a resistance of 1 Ω are connected to a battery. The Ammeter indicates 3 A when the key is inserted. What is the reading of voltmeter?

Answer 1

Answer:

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Answer 2

In this circuit, 8Ω and 12Ω are connected in parallel, and this parallel resistors are connected in series with 7.2Ω.

8Ω and 12Ω are in parallel, their equivalent resistance:

$\frac{r}{1} = \frac{1}{8} + \frac{1}{ 12 } = \frac{5}{24} \\ R=4.8Ω \\ Now, Equivalent resistance (series connection) of the circuit =4.8+7.2=12Ω \\ \\ V=IR \\ I=V \frac{v}{r} =\frac{12}{6} =0.5a \\ Potential Difference across 7.2Ω resistor =I×R=0.5×7.2=3.6V$

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