A cylinder of weight `W` and radius `R` is to be raised onto a horizontal step of height `h` as shown in Fig. A rope is wrapped around the cylinder and pulled horizontally with force `F`. Assuming the cylinder does not slip on the step, find the minimum force `F` necessary to raise the cylinder.

Answer

`(Wsqrt(2gh-h^(2))/((2R-h))`

Explanation

`d=sqrt(R^(2)-(R-h)^(2))=sqrt(2Rh-h^(2))`
Taking torque about `P, tau_(F)gttau_(W)`
For minimum `F, Wd=F(2R-h)`
or `F=(Wsqrt(2Rh-h^(2)))/((2R-h))`