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Question
If 220 V potential difference is applied across an electric bulb, a current of 0.45 A flows in the bulb. What must be the power of the bulb?
Options
99 W
70 W
45 W
22 W
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Solution
99 W
Explanation:
Given:
Potential difference = 220 V, Current = 0.45 A
Power (W) = Potential difference (V) × Current (A)
= 220 × 0.45 W
= 99 W
So, the bulb must be of power 99 W.
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