(a) The commercial unit of energy is kilowatt hour (kW h).

1 kW h = 3.6 x 10^6 J

(b) Given P = 60 W,

t = 10 h,

W = ?

W = P x t

= 60 x 10

= 600 W h

= 0.6 kW h.

(a) The commercial unit of energy is kilowatt hour (kW h).

1 kW h = 3.6 x 10^6 J

(b) Given P = 60 W,

t = 10 h,

W = ?

W = P x t

= 60 x 10

= 600 W h

= 0.6 kW h.