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CBSE Class 9 Answered

A boy of mass 50kg running at 5 m/s jumps on to a 20kg trolley travelling in the same direction at
Asked by | 23 Apr, 2009, 05:59: PM
answered-by-expert Expert Answer

Using conservation of momentum

MV+mv = (M+m)v'

Where :
M- Mass of the boy - 50kg
m- mass of the trolley - 20kg
V- velcoity of the boy - 5m/s
v- velocity of the trolley-1.5m/s
v' - common velocity - x

(50+20) x=(50x5 +20x1.5)

x= 4m/s.

Hence, the common velocity of the 4m/s.

Answered by | 30 Apr, 2009, 01:17: PM

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