Work energy theorem sys work done by all the force is equal to change in kinetic energy" In the diagram, a disc of mass `M` and radius `R `is rolling without slipping on a rough fixed inclined `AB = l, V =` velocity of disc at `B`.

Choose the correct option(s)

Options

A. Total work done by frictional force `(W_(f))` is `Mg//sintheta`
B. Total work done by frictional force `(W_(f))` is `(3)/(4)MV^(2)`
C. Total work done by frictional force `(W_(f))` is `-Mglsintheta`
D. Total work done by frictional force `(W_(f))` is zero

Answer

A, B, C

Explanation

`mgl sintheta = (1)/(2)mv^(2) + (1)/(2)(mR^(2))/(2)((v)/(R))^(2)`
`mgl sintheta = (3)/(4)mv^(2)`
`v = sqrt((4glsintheta)/(3))`
Work done by friction is `0`.