Question

An electric iron of resistance 9 ohm draws 12 A from the main service line in 2.5 hours. Calculate the rate at which heat is developed in the heater

Answer 1

Explanation:

The resistance of the electric heater (R) = 8 Ω

Current drawn (I) = 15 A

Time = 2 hrs

T = 120 min x 60

Time (T) = 7200 secs

The rate of heat produced by the device in terms of power is expressed as

P= I2R

P = 15 x 15 x 8

P = 1800 watt

Answer

P= 1800 watt