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Anya lifts a ball high above her head and drops it. The ball bounces up and down. She observes that the ball loses height every time it bounces. How can this situation be explained?

Respuesta :

Answer:

Part of the mechanical energy of the ball is converted into heat

Explanation:

The mechanical energy of the ball is the sum of its gravitational potential energy and its kinetic energy:

E = U + K

In an ideal world, where there is no friction or air resistance, the mechanical energy of an object is always constant. This means that as the ball falls down, its potential energy converts into kinetic energy, and when it bounces up, the kinetic energy converts into potential energy, but the total mechanical energy E remains constant. In this case, the ball would always bounce back at its original height from where

In the real world, however, there are frictional forces acting on the ball: as a result, part of the mechanical energy is converted into heat due to the effect of these frictional forces, and therefore at every bounce the ball will reach a height which is lower than the height reached at the previous bounce - eventually, the ball will stop on the floor. The frictional forces acting in this case are:

- The friction between the ball and the floor as the ball hits the floor

- The air resistance, which slows down the ball