Q. 304.6( 16 Votes )

# A car weight 20000 N climbs up a hill at a steady speed of 8 m/s, gaining a height of 120 m in 100 s. Calculate:

(a) Work done by the car.

(b) Power of engine of car.

Answer :

(a) Weight of the car (W) = 20000 N

Height = 120 m

Time taken (t) = 100 s

Work done by car = Force × displacement

= 20,000 × 120

= 2400000 KJ or 2.4 x 10^{6}J

(b) Power = work done/ time

= 2400000/100

= 24 KW

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