`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
