This experiment is almost magical in nature. The purpose is to demonstrate that the centre of gravity is the balancing point of an object.
Things Required:
Yardstick (metre stick)
Hammer (wooden handled hammer works best)
String, 12 inches (30 cm)
Directions:
Hold the ends of the string together and tie a knot about 2 inches (5 cm) from the ends. Insert the hammer and yardstick through the loop. Position the end of the yardstick on the edge of a table. The handle of the hammer must touch the yardstick and the head of the hammer will extend under the table. Change the position of the hammer until the whole unit-yardstick, string, and hammer-balances.
This Is What Happens:
The unit balances with only a small amount of the yardstick touching the table.
Science Behind It:
The hammer string and yardstick all act as a single unit with a centre of gravity. The centre of gravity is the point where any object balances. The dashed line in the diagram allows you to visualize the centre of gravity. The heavy hammer head counter-balances the weight on the left side of the balancing point.
