Two bulbs 25 W, 220 V and 100 W, 220 V are given. Which has higher resistance?

Question

G1 Physics · Accepted Answer

Step 1: At equal rated voltage, resistance R = V²/P. Step 2: 25 W bulb R₂₅ = 220²/25; 100 W bulb R₁₀₀ = 220²/100. Step 3: R₂₅ = 4R₁₀₀; 25 W bulb has higher resistance.