Q19 of 330 Page 58

A bulb is rated as 250 V; 0.4 A Find its:

(i) power, and (ii) resistance.

(i) We know that

V = 250V, I = 0.4amp


Power = VI = 250X0.4 = 100watt


(ii) We have,


V = 250V, I = 0.4amp


We know that


P = I2R


100 = 0.42XR


R = 625ohm


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