A ball moving with a velocity ef 10 impinges on a vertical wall at an angle of 45° with the normal to the wall. After the collision, the ball moves on the other side of the normal at an angle of 45° with the normal. The coefficient of restitution is 0.5. The velocity of the ball after the collision will be

Options

A. 2 `ms^(-1)`
B. 3`ms^(-1)`
C. 5 `ms^(-1)`
D. 50 `ms^(-1)`

Answer

c

Explanation

Here the coefficient of restitution
`e=("Normal component of R.V after collison")/("Normal component of R.V before collison")`
`e=0.5=(v cos 45^(@))/(10 cos 45^(@))=(v)/(10)`
or `v=10xx0.5=5 ms^(-1)`