Racing on an inclined plane

What you can do here
You have an inclined plane and two objects of the same weight, but different mass distribution. Roll them to the START position and release both of them exactly at the same time. Observe their movement.


How it works
According to the law of conservation of energy, when an object rolls down an inclined plane, kinetic energy increases by as much as potential energy decreases. In turn, kinetic energy is made up of translational kinetic energy and rotational kinetic energy. In case of an object with a mass distributed further from the rotation axis, rotational kinetic energy forms a larger part of kinetic energy and translational kinetic energy forms its smaller part, therefore this object rolls down more slowly.


Interesting facts
This effect is used by pirouetting dancers. When they pull their arms towards their body, they spin faster. You can do a similar experiment in the Small merry-go-round.