Flooded Cricket Ball Mystery

The story

Kabir played cricket in Aundh one rainy monsoon day. He always believed cricket balls never sank; they seemed heavy and solid enough. But during his match, the ball landed in deep floodwater and floated for a bit. Suddenly, it vanished under the surface. Kabir was shocked and tried to retrieve it with a stick but couldn’t find it. He wondered if the rain was magical. His Aaji saw his confusion and pointed out that the ball had soaked up a lot of water. By the next day, Kabir noticed that his waterlogged ball no longer floated at all. He knew he couldn’t blame his friend Chintu for this mystery. The question remained: would a tennis ball ever sink, too?

The science

When the cricket ball first landed in the water, the air trapped inside kept its total density less than that of water. This allowed the buoyant force of the water to keep the ball afloat. However, as water entered through the seams and replaced the air inside, the ball became heavier. Its average density increased beyond that of water. When the ball’s weight became more than the upward buoyant force, it sank. This cause and effect is explained by Archimedes’ Principle, which relates floating and sinking to density and displaced water.

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