Question

In the circuit shown, reading of the voltmeter connected across $400\Omega$ resistance is 30 V. If it is connected across $300\Omega$ resistance then reading will be:

• A. $45V$
• B. $32.5V$
• C. $22.5V$
• D. $18V$

Answer 1

The correct option is C $22.5V$

Current trough 400 $\Omega$ is $I=30/400=3/40A$
As 400 $\Omega$ and 300 $\Omega$ are in series so same current I will pass through them.
Voltage across 300 $\Omega$ is $V^{\prime }=300I=300\left(3/40\right)=22.5V$