question_answer

Two 220 V, 100 W bulbs are connected first in series and then in parallel. Each time the combination is connected to a 220 V AC supply line. The power drawn by the combination in each case respectively will be:    [AIPMT 2003]

A) 200 W, 150 W

B) 50 W, 200 W

C) 50 W , 100 W

D) 100 W, 50 W

Correct Answer: B

Solution :

Let,

and

and

Case I: When two bulbs are connected in series.

In series,

Hence,

Case II: When two bulbs are connected in parallel.

In parallel,

Hence,

Alternative:

For series

For parallel