AIIMS 2018 Physics Power and Energy MCQ Question

When the bulbs are connected in parallel, they both receive the full voltage of 220 V, leading to heat production proportional to their power ratings: $Q_{parallel} = P \cdot t$. Thus, the heat produced by the 500 W bulb is 500 and by the 200 W bulb is 200, giving a ratio of $500 : 200 = 5 : 2$. In series, the voltage across each bulb is divided based on their resistances, resulting in a different heat ratio. The effective power for each bulb in series is calculated using $P = \frac{V^2}{R}$, leading to a heat ratio of $5 : 2$ for both configurations, thus yielding a final ratio of $5/2 : 5/2$ in option B. Other options are incorrect as they misrepresent the ratios derived from the heat calculations in both configurations.