Cut out pie pan demonstrates path when centripetal force disappears

• G+5+25

A cut out pie plate simulates the effect of the cessation of normal force (such as gravity and a planet). A ball rolled around a pie plate travels in a straight line when it reaches the edge of the pie plate, obeying Newton’s second law. Many students will evidence a misconception that the ball will continue traveling in a circle after it leaves the edge of the pie plate. This can be addressed using a clicker question such as: If I roll a ball around in a circle will it: 1. Continue traveling in a curve when it reaches the edge 2. Travel in a straight line 3. Curve the other direction