Question

Two electric lamps each of 100 watt 220v are connected in series to a supply of 220 volts. The power consumed would be:

• A. 100 watts
• B. 200 watts
• C. 25 watts
• D. 50 watts

Answer 1

The correct option is D 50 watts

P$=\frac{V^2}{R}$ ...(1)
In series,
$R_{eq}=R_1+R_2⟹R_{eq}=2R$
Hence P is also halved,

$P^{\prime }=\frac{P}{2}=50Watts$