Question

Two resistors $400\Omega$ and $800\Omega$ are connected in series with a 6 V battery. the potential difference measured by voltmeter across $400\Omega$ resistor is:

• A. $2V$
• B. $1.95V$
• C. $3.8V$
• D. $4V$

Answer 1

The correct option is A $2V$

Total resistance of the circuit (series combination) $R_s=R_1+R_2$

$\therefore$ $R_s=400+800=1200\Omega$

Current, $I=\frac{E}{R_s}=\frac{6}{1200}$

$I=0.005A$

Potential difference across $R_1$, $V^{\prime }=I{R}_1$

$\therefore$ $V^{\prime }=0.005\times 400$

$V^{\prime }=2V$