Q. Electric bulb $50\ W$-$100\ V$ glowing at full power are to be used in parallel with battery $120\ V,\ 10\ \Omega.$ Maximum number of bulbs that can be connected so that they glow in full power is
A) 2
B) 8
C) 4
D) 6
Explanation
(c) When each bulb is glowing at full power,
Current from each bulb $= i^{'} = \frac{50}{100} = \frac{1}{2}A$
So main current$\ i = \frac{n}{2}A$
Also$\ E = V + ir \Rightarrow 120 = 100 + \left( \frac{n}{2} \right) \times 10 \Rightarrow n = 4$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.