An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.
Rate of heat produced by a device is given by the expression for power as, P= I 2R Where, Resistance of the electric heater, R= 8 Ω Current drawn, I = 15 A P= (15)2 x 8 = 1800 J/s Therefore, heat is produced by the heater at the rate of 1800 J/s.
