A block of mass M is held against a rough vertical wall by pressing it with a finger . If the coefficient of friction between the block and the wall is mu and the acceleration due to gravityis g , calculate the minimum force required to be applied by the finger to hold the block against the wall.

A block of mass M is held against a rough vertical wall by pressing it

1.	A block of mass M is held against a rough vertical wall by pressing it with a finger . If the coefficient of friction between the block and the wall is mu and the acceleration due to gravityis g , calculate the minimum force required to be applied by the finger to hold the block against the wall.
Answer» Solution : For the block not to FALL f=Mg But `f=MU R=muF so` `muF=Mg` `F=(Mg)/(mu)`.