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Question
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 ?
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Solution
Common velocity just after the collision if they move off together will be :
`v = ((m_1 xx u_1)+(m_2+u_2))/(m_1+m_2)`
`m_1 = 500` kg,
`u_1` = 4 m/s
`m_2` = 1500 kg
`u_2` = 2 m/s
`v = ((500+4)+(1500xx2))/(500+1500)`
⇒ `v = (2000+3000)/2000`
⇒ `v = 5000/2000`
⇒ `v = 5000/2000`
⇒ v = 2.5 m/s
This is their common velocity after collision .
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