Question

Several electric bulbs designed to be used on a 220 V electric supply are rated 20 W each. How many lamps can be connected in parallel with each other across the two wires of 220 V line if the maximum allowable current is 5 A?

• A. 50
• B. 110
• C. 55
• D. 60

Answer 1

The correct option is C 55

For a Bulb, $Vi=P=20W$

$\therefore i=\frac{P}{V}=\frac{20}{220}=\frac{1}{11}A$

$I=ni\Rightarrow 5A=n\left(\frac{1}{11}A\right)$

$\therefore n=55$