Q. 574.4( 11 Votes )

# A truck of mass 500 kg moving at 4 m/s collides with another truck of mass 1500 kg moving in the same direction at 2 m/s. What is their common velocity just after the collision if they move off together?

Answer :

Let

m1=500,

m2=1500

u1=4m/s

u2=2m/s

v1=v2 (since after collision they stuck together)

According to law of conservation of momentum,

m1u1 + m2u2 = m1v1 + m2v2

500 x 4 + 1500 x 2 = (500 + 1500) v

5000 = 2000v

v = 5000/2000

v = 2.5m/s

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