A ball moving with a speed of `9 m s^(-1)` strikes an identical stationary ball such that after the collision the direction of each ball makes an angle of `30^@` with the original line of motion. The speeds of two balls after the collision is

Options

A. `5.2 ms^(-1)`
B. `0.52 ms^(-1)`
C. `52 ms^(-1)`
D. `26 ms^(-1)`

Answer

A

Explanation

The given conditionis can be shwon as
After collision, `mv_(1)sintheta = mv_(2)sintheta`
`rArr v_(1)=v-(2)=v`
`rArr 2mv cos 30^(@) = 9`
`rArr v=(9/sqrt(3)) = 3sqrt3) = 5.2ms^(-1)`