Question

DEFINE THE UNIT OF ELECTRICALENERGY. WHAT IS THE COMMERCIAL UNIT OF ELECTRICAL ENERGY?

Answer 1

The total electric work or energy supplied by the source of e.m.f. in maintaining the current in an electric circuit for a given time is called electric energy consumed in the circuit.
Therefore, Electrical energy , W = V I t = P.t
Therefore. electrical energy = electric power X time
S.I. unit of electrical energy is joule, where
1 Joule = 1 volt X 1 Ampere X 1 sec
= 1 watt X 1 sec

The commercial unit of electrical energy is kilowatt- hour (kWh).