Problem 529 | Friction

Problem 529
As shown in Fig. P-529, a homogeneous cylinder 2 m in diameter and weighing 12 kN is acted upon by a vertical force P. Determine the magnitude of P necessary to start the cylinder turning. Assume that μ = 0.30.
 

529-cylinder-again.gif

 

Solution 529

 

Hi sir. Goodmorning. Bakit po pala natanggal ung normal force sa horizontal surface when the cylinder turns due to force "P" and ung normal force sa may inclined surface ay hinde? I was thinking about the cylinder would be on the same spot po pa rin kasi if turned by a force "P" since angle of friction=tan-1(0.3)= 17° is lesser than the angle of the inclined plane.