Launching A Ping Pong Ball With A Dropper Popper

This activity is designed for students to compare and contrast gravitation potential energy and elastic potential energy. All of Newton's Laws are demonstrated in some manner. Key concepts include: Students will be able to distinguish between elastic potential energy, gravitational potential energy, and kinetic energy. Students will be able to explain why the ping pong ball travels higher when dropped with the Dropper Popper. Students will be able to identify where Newton's Laws apply in the demonstration.

Students will utilize the skills of critical thinking, observation, synthesis of ideas, and questioning.

Vocabulary words: elastic potential energy, gravitational potential energy, kinetic energy, work.

This activity can be done as a demonstration by teacher or as a guided inquiry in small groups. As a teacher demonstration it would take about 20 minutes with question and answering. As a student activity it would take about 30-40 minutes including the write-up. The activity fits at any time during a unit on Work and Energy or Newton's Laws in the physical science or physics classroom. It works well as an introduction investigation (there is a definite "wow" factor here), a review, or even as a final assessment with students describing what is happening and why.

I introduce a short review lecture-questioning about kinetic and potential energy. Then students are put into small groups and each group is given a ping pong ball and a Dropper Popper (looks like a hollow rubber ball cut in half, available from Educational Innovations). Students are then asked to drop the ping pong ball from various heights and watch how far the ball rebounds. They are then asked to do the same with the Dropper Popper in its normal configuration and inverted. Students are then asked to figure out how to get the Dropper Popper to cause the ping pong ball to hit the ceiling. Each group needs a ping pong ball, Dropper Popper and meter stick. NOTE: Safety goggles should be worn by younger students.

This activity is adapted from Educational Innovations, Inc. www.teachersource.com

This activity can get a little chaotic if done in small groups. There is a definite "wow" factor and students want to continually repeat the process. Safety goggles should be worn by younger students and older students told to watch out for others. Doing this activity in a gym or outside is excellent because the ping pong ball travels very high and will not rebound off the ceiling.

I do informal assessment during the activity to see if students are on task and using correct vocabulary words. Afterwards students are asked to write and turn in a one page description and explanation of what happens with the Dropper Popper and ping pong ball. The write up must include vocabulary words and Newton's Laws. At the end of unit test, students are asked questions referring back to the Dropper Popper activity.

II. Physical Science 9-12; C. Energy Transformation; D. Motion.