Question

What force parallel to the inclined is required to push a 40 kg up on a 50^o inclined plane if the coefficient of friction (static) is 0.3.

Answer 1

$\vec F+m\vec g+\vec N+\vec{F_{fr}}=\vec 0,$

$Ox:F-F_{fr}-mg\sin\alpha=0,$

$Oy:N=mg\cos\alpha,$

$F_{fr}=\mu N,$

$F=mg(\mu\cos\alpha+\sin \alpha)=376~N.$