Archimedes’

• Archimedes was a Greek scientist.

• He noticed the water in the bathtub overflowed when he stepped into it.

• He ran through the streets, shouting "Eureka.”

• He formulated the principle of buoyancy.

Take a piece of stone and tie it to one end of a rubber string or a spring balance. Suspend the stone by holding the balance or the string. Note the elongation of the string or the reading on the spring balance due to the weight of the stone. Now, slowly dip the stone in the water in a beaker.

The reading of the balance or the elongation of the string decreases as the stone gradually lowers in the water. At first, the elongation in the spring or the spring balance is due to the weight of the stone. But when it dipped into the water, some force acted on the stone in an upward direction, thus causing decreases in elongation and spring balance reading. As a result, the net force on the string decreases, and hence the elongation also decreases. The upward force exerted by water is known as the force of buoyancy. As the stone is immersed, an equal amount of water, similar to the weight of the stone, is collected in the beaker. This proves Archimedes' principle.