Inertia: Penny Passengers

Place a penny on top of a small toy car.

Roll the car so it runs into a thin book or piece of corrugated cardboard.

Observe the car and the penny.  What can you learn from this activity about the importance of seat belts?

What difference does a seat belt make?  Try again, using a small piece of tape to hold the penny on the car.   

Do different coins respond differently?  Dimes are lighter than pennies, quarters are heavier.

Note:
You need to push the car very gently, or you'll observe a different form of inertia - the car will move out from underneath the penny and the penny will drop to the table.