Question

A lamp uses 500j of electric energy in 20 sec what is the power of lamp. If lamp works 2 hrs per day for 15 days, calculate the unit consumed by lamp.

Answer 1

ANSWER:-

we know:-

Power=Energy /time

so, acc. to this ques.

P=500/20=25j/s

so,p of lamp =25j/s or watt

In 2nd case it works for 2 hrs =25/1000=1/40=0.025kilowatt

We know p=e/t

0.025=e/2

e= 0.05kwh

so, in 15 days the unit is

0.05*15 =0.75kwh