a girl if mass 40 kg sit on the trolley of mass 5kg. The initial speed of the trolley is 5 metre per second when the force is applied the trolley comes to the rest after travelling the distance of 10.(1) find the work done on the trolley.(2)find the work done by the girl on the trolley.
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a girl having a mass of 35kg sits on a trolley of mass 5 kg. the trolley is given an initial velocity of 4m/s by applying a force. the trolley comes to rest after travelling a distance of 16m. how much work is done on the trolley? how much work is done by the girl?
Given:
Mass of girl = 35 kg
Mass of trolley = 5 kg
Total mass, m = (35 + 5) = 40 kg
u = 4 m/s
v = 0
s = 16 m
By equation,
v 2 = u 2 + 2as
0 = (4)2 + 2a (16)
32a = –16
a = –0.5 m/s2
Force exerted on trolley,
F = ma
= 40 × 0.5 = 20 N
Work done on trolley W = FS = 20 N x 16 m
= 320 J
Work done by the girl, W = FS
= mass of girl × retardation × S
= 35 × 0.5 × 16
= 280 J