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If the current in an electric bulb increases by 1 %, what will be the change in the power of a bulb ? [Assume that the resistance of the filament of a bulh remains constant] |
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Answer» INCREASES by 1% Power of a bulbP = `I^(2) ` R , where R = Resistance 0 FORCE Now, increase or 1% of current , NEW current I. = I + 1% ,I = I + 0.01 I I. = 1.01 I New Power P.= `I.^(2) ` R P.= `(1.01I)^(2) R = 1.02 I^(2)` R `(P.)/(P) = (1.02 I^(2)R)/(I^(2) R)` P.= 1.02 P = P + 0.02 P = P + 2% P Change in the power of bulb= 2% |
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