Q 12-03-268JEE MainJEE Main 2019 (11 Jan, Shift 1)Easy
Two equal resistances when connected in series to a battery, consume electric power of $60$ W. If these resistances are now connected in parallel combination to the same battery, the electric power consumed will be:
Answer: (B) $240$ W
Series: $P_s = \dfrac{V^2}{2R} = 60$ W. Parallel: $P_p = \dfrac{V^2}{R/2} = 4\times\dfrac{V^2}{2R}$.
$$P_p = 4\times60 = 240\ \text{W}$$
Solution by Sreeraj P, M.Sc Physics