I was given this question in a practice assignment; A 31.0 kg child on a swing reaches a maximum height of 1.92 m above her rest position. Assuming no loss of energy: 1.At what point during the swing will she attain her maximum speed? 2.What will be her maximum speed through the subsequent swing? 3.Assuming this maximum height was the result of one push from her parent, what was the average force exerted by the parent if s/he pushed over a distance of 152 cm? I got the first 2 questions no problem. But for question 3, Can I simply use the equation W=Fcosθd. Where W would be equal to the gravitational potential so I would have mgh=fd, rearrange and solve, or am I missing something?