Question

an electric kettle of 400watt is is used to heat water everyday for2.5 hours calculate the number of unit of electrical energy consume by it in 20 days

Answer 1

P=400w
=400/1000 kw/h
T=2.5h * 20
=50h
E=P/T
E=400/1000 * 50
=20 kw/h
=20 unit

Answer 2

1*40/1000*2.5*20 = 2J