Question

An electric lamp whose resistance is 10 ohm and a conductor of 2 ohm resistance are connected in series with a 6 V battery. The total current through the circuit and the potential difference across the electric lamp are

• A. 3.6 A, 6 V
• B. 0.5 A, 5 V
• C. 2.0 A, 0.2 V
• D. 0.3 A, 3 V

Answer 1

The correct option is B 0.5 A, 5 V

In series combination,
$R=R_{Lamp}+R_{conductor}=10\Omega +2\Omega =12\Omega$
$I=\frac{V}{R}=\frac{6v}{12\Omega }=0.5A$
$\Rightarrow V_{Lamp}=IR=0.5\times 10=5V$