This can demostrates conservtion of energy and the conversion of energy from potential to kinetic energy. Inside is a weight connected to two ruberbands. When the can is rolled across the floor the weight will stay in place as the rubberbands twist storing energy. As the can reaches the end of its roll the rubberbands will unravel and the can will roll back to you.

Equipment
Coffee Can		Rubber Band		2 Pencils
Masses