A roller of mass 300kg rests against a step of height 20cm. If the radius of the roller is 50cm find the minimum horizontal force to be applied passing through its centre of mass to take the roller on the step.

A roller of mass 300kg rests against a step of height 20cm. If the rad

1.	A roller of mass 300kg rests against a step of height 20cm. If the radius of the roller is 50cm find the minimum horizontal force to be applied passing through its centre of mass to take the roller on the step.
Answer» Solution :Taking the moments of forces about .O. h=0.2m, R=0.5m , `X^(2)=R^(2)-(R-h)^(2)` `x=sqrt(R^(2)-(R-h)^(2))=0.4m` To climb up the step, MOMENT due to HORIZONTAL force `ge` moment due to weight. `FXX(R-h) ge MGX` `F ge (mgx)/(R-h)` `F ge (300xx9.8xx0.4)/(0.3)=3920N`