Law of Conservation of Energy

The law of conservation of energy states that energy cannot be created or destroyed, it can only be transformed from one form to another. In other words, the total energy of a closed system remains constant. This law is applicable to all forms of energy, including mechanical, electrical, thermal, and chemical energy.

Conservation of Energy in a Falling Object

When a body of 10kg is dropped from 4m height, the potential energy of the body is converted into kinetic energy as it falls towards the ground. The conservation of energy can be demonstrated in tabular form as follows:

Height | Potential Energy | Kinetic Energy | Total Energy
--------|----------------|----------------|----------------
4m | 0 J | 0 J | 98 J
3m | 294 J | 0 J | 294 J
2m | 196 J | 98 J | 294 J
1m | 98 J | 196 J | 294 J
Just above the ground| 0 J | 294 J | 294 J

Explanation

At the initial height of 4m, the body has potential energy but no kinetic energy. As it falls, the potential energy decreases and the kinetic energy increases. At a height of 3m, all the potential energy has been converted into kinetic energy. At a height of 2m, half of the potential energy has been converted into kinetic energy. At a height of 1m, most of the potential energy has been converted into kinetic energy. Just above the ground, all the potential energy has been converted into kinetic energy.

The total energy of the system (body and Earth) remains constant throughout the fall. At all heights, the total energy is equal to the sum of potential and kinetic energy. When the body reaches the ground, all the potential energy has been converted into kinetic energy, and the total energy of the system remains constant.

In conclusion, the law of conservation of energy holds true in the case of a falling object. The potential energy of the body is converted into kinetic energy as it falls towards the ground, and the total energy of the system remains constant.