An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours

Question 17:

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.

Answer:

Here Given that Resistance of the electric heater (R) = 8 Ω

Current drawn (I)= 15 A

We know that P = I²R

                         = 15×15×8

                          = 1800w or J/s

∴ Heat is produced by the heater at the rate of 1800 J/s.