A child on a sledge is being pulled along a horizontal path by its parent. The child and sledge have a combined mass of 18kg and there is a normal contact force of 135 N. Given there is no resistance to motion and the parent pulls with a force of F N at an angle 25 degrees to the horizontal, then what is F?

Question

A child on a sledge is being pulled along a horizontal path by its parent.  The child and sledge have a combined mass of 18kg and there is a normal contact force of 135 N. Given there is no resistance to motion and the parent pulls with a force of F N at an angle 25 degrees to the horizontal, then what is F?

mathmate · Answer

$$\sum F _{y} = 0$$
So
mg - N = Fsin(theta)
Solve for F.