A ladder AP of length `5m` inclined to a vertical wall is slipping over a horizontal surface with velocity of `2m//s`, when A is at distance `3m` from ground. What is the velocity of COM at this moment?

Answer

A, B

Explanation

`y=sqrt(L^2-x^2)implies(dy)/(dt)=-(x)/(sqrt(L^2-x^2))(dx)/(dt)`

`=-(3xx2)/(4)=-3/2m//s`
`V_(CM)=sqrt(((1dx)/(2dt))^2+(1/2(dy)/(dt))^2)`
`=sqrt((1)^2+(3/4)^2)=1.25m//s`