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Question
A bulb is rated as 250 V; 0.4 A. Find its : (i) power, and (ii) resistance.
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Solution
Given:
V = 250 V
I = 0.4 A
Power, P = VI
= 250 x 0.4
= 100 W
Resistance, R = `R=P/(I2) `
= `100/(0.4)^2`
= 625 Ω
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