Question

Two electric bulbs A and B are designed for the same voltage. Their power ratings are P_A and P_B respectively, with P_A > P_B. If they are joined in series across a V-volt supply, 

(a) A will draw more power than B 

(b) B will draw more power than A

(c) the ratio of powers drawn by them will depend on V

(d) A and B will draw the same power 

Answer 1

Correct answer is: (b) B will draw more power than A

R = V²/R. The bulb with higher power rating has lower resistance, and vice versa. When the bulbs are joined in series, they draw the same current. As P = i²R, the bulb with the lower power rating draws more power.