Where the kinetic energy went...
The kinetic energy turned into other kinds of energy as the top slowed down. The spinning top was rubbing against the table under it as it spun. Because the top and the table are moving against each other friction causes the molecules in the top of the table to vibrate more. The molecules in the table want to spin with the top! As the molecules slow down and stop vibrating they give up this vibrational energy as heat.
If you want another example of friction, think about what happens as you rub your hand really fast across a carpet (other than generating massive amounts of static electricity!). Your hand gets warm! This is because the carpet wants to try to move with your hand but it can't. This is just like the top slowing down.
There are three types of kinetic energy that exist. Can you think of three different types of motions that could lead to these three kinds of kinetic energies?
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