An incandescent bulb rated as 100 W at 110 V is connected to a 220 V power supply. The power that dissipates in the bulb would be :
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EPFO EO AO 2023
Explanation:
- The power dissipated in a resistive load like a bulb is given by the formula P = V2/R. You need to find the resistance (R) first using the rated values.
- For the 100 W at 110 V bulb, R = 1102/100 = 121 Omega
- Now connect it to 220 V: P = 2202/121 = 400 W
- When the voltage is doubled, power dissipation quadruples due to the squared relationship in the formula.
- Correct Answer: 400 W
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By: Parvesh Mehta