An electric heater of resistance `8 Omega` draws `15 A` from the service mains for `2` hours. Calculate the rate at which heat is developed in the heater.

Explanation

Heat developed in the heater is given by H = `I^(2)` R f Where, I = 15 A, R = 8 `omega` and time t = 2 hours The rate at which heat is developed is given by : `P= (H)/(t )=I^(2)Rt//r =I^(2)R`
`= (15)^(2)xx 8` = 1800 J`//`s = 1800W