Two billiard balls undergo a head-on collision. Ball 1 is twice as heavy as ball 2. Initially, ball 1 moves with a speed `v` towards ball 2 which is at rest. Immediately after the collision, ball 1 travels at a speed of `v//3` in the same direction. What type of collision has occured?

Options

A. inelastic
B. elatic
C. completely inelastic
D. Cannot be determined from the information

Answer

B

Explanation

Using conservation of linear momentum
`mv_(2)+2m(v)/(3)=2mv+m(0)`
`rArrv_(2)=(4v)/(3)`
Now `e=((4v)/(3)-(v)/(3))/(v-0)=1`
`rArr` collision is elastic