(a) State law of conservation of energy.
(b) Establish the relation between SI unit of energy and commercial unit of energy.
© A toy car is displaced through 5 m on application of a force of 7 N. Let us take it that the force acts on the object through the displacement. What is the work done in this case?
Energy can neither be created nor destroyed i. e., the total energy of the system remains conserved.
SI unit of energy = joule, Commercial unit of energy = kW h
1 kW h= 1000 W x 1 h = 1000 x 3600 W = 3600000 J
Work = FxS = 7x5 = 35 J