A system is shown in the figure. Block `A` moves with velocity `10m//s`. The speed of the mass `B` will be `:`

Options

A. `10sqrt(2) m//s`
B. `5sqrt(3) m//s`
C. `(20)/(sqrt(3))m//s`
D. `10m//s`

Answer

C

Explanation

`(v_(1) +v_(2))xx(1)/(sqrt(2))=10`
`v_(1) cos 15^(@) = v_(2) cos 75^(2) rArr v_(1) = v_(2) xx (sqrt(3)-1)/(sqrt(3)+1)`
velocity of B `= sqrt(v_(1)^(2)+v_(2)^(2))=(20)/(sqrt(3)) m//s`