4.110 - A 3m uniform plank of weight 203 N rests on two joists as shown.The coefficient of static friction between the joists and the plank is 0.40. (a) Determine the magnitude of the horizontal force...

4.110 - A 3m uniform plank of weight 203 N rests on two joists as shown.
The coefficient of static friction between the joists and the plank is 0.40.

(a) Determine the magnitude of the horizontal force P
required to move the plank.

(b) Solve part a assuming that a single
nail driven into joist A prevents motion of the plank along joist A.