Question

A small ball of mass m is attached to the end of the string of length l=1 m whose other end is fixed. From its lowest position, the ball is given a kinetic energy ml/5. the net acceleration (in `m//s^(2)`) of the ball at the instant when the string makes an angle `theta ` of `37^(@)C` with the downwards vertical is___________

Answer 1

Correct Answer - 6
by energy conservation
`v_(1)^(2)=v_(0)^(2)-2gl(1- cos theta)`
=0
tangential `a_(t)=g sin theta`

`=6 m//s^(2)`
Radial `a_(r)=0`
Resultant acceleration `=sqrt(a_(r)^(2)+a_(t)^(2))=6 m//s^(2)`