When a current of 4.0 A passes through a certain resistor for 10 minutes, 2.88 x 104 J of heat are produced. Calculate:

(a) the power of the resistor.


(b) the voltage across the resistor.

(a), Here it is given,

I = 4 amp,


t = 10 min = 10 x 60 = 600sec, H = 2.88x104J


We Know that according to Joule's law of heating


H = I2RT


28800 = 42xRx600


R = 3ohms


We know that


P = I2xR


= 42x3


P = 48W


(b) Here we have to find the potential difference, V = ?


We know that


V = IR


V = 4x3


V = 12V


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