A loop of radius 3 meter and weighs `150kg`. It rolls along a horizontal floor so that its centre of mass has a speed of `15 cm//sec`. How much work has to be done to stop it -

Options

A. `3.375 J`
B. `7.375 J`
C. `5.375 J`
D. `9.375 J`

Answer

A

Explanation

Required work `=` Total K.E.
`= 1/2 mv^(2) (1+(k^(2))/(R^(2)))`
`= 1/2 Mv^(2) [1+(k^(2))/(R^(2))]`
`= 1/2 xx 150 xx (0.15)^(2) (1+1)`
`= 3.375 J`