At a playground, two kids are playing at the swings. One is rotating the swing (with the other child on it) to twist the chains together.

Question

At a playground, two kids are playing at the swings. One is rotating the swing (with the other child on it) to twist the chains together. Once the swing is let go, the child on the swing whirls round and round as the swing is untwisted. The child loses his shoe just after his feet start going at a speed of 3.5m/s. If the shoe is 0.50m from the pivot point of the rotation and has mass of 0.21kg, how much centripetal force is acting on the shoe just before it slips off?

Answer 1

Givens: (Write down what you know)

m=0.21kg

v=3.5m/s

r=0.50m

What am I looking for? F_c on the shoe at the moment of my givens

Do I have a formula that relates the givens to what I want?

F_c=mv²/r

Plug in

F_c=(0.21)(3.5)²/0.50

In cases where you don't have a single formula that has everything you want, do you have a formula using some or all of your givens that gives you something that is useful?