The diagram shows a rough plank resting on a cylinder with one and of the plank on rough ground. Negtect friction between plank and cylinder. Draw digrams to show
(a) the force acting on the plank,
(b)the force acting on the cylinder.

Explanation

`w_(1) =` weight of cylinder
`w_(2) =` weight of plank
`N_(1) =` normal reation between cyclinder and plank
`N_(2) =` normal reation on cyclinder from ground
`N_(3) =` normal reation on plank from ground `f_(1) =` force of friction on cyclinder from ground `f_(2) =` force of friction on plank from ground