(a) State a

(a) The rate of doing work is called as the power. The SI unit of power is Watt denoted by W.

1 Watt is the power of appliances that consume the energy at the rate of 1 joule per second.

(b) Given

Mass of brick = 2.5 kg

⇒ Weight = mg = 2.5×10 = 25 N

Weight of 10 bricks = 25×10 = 250 N

Height (h) = 20 m

Time (t) = 50 s

Power =

⇒ Power =

Power spent in carrying bricks is 100 Watt.