Question

A body is falling freely under the action of gravity alone in vacuum. Which of the following quantities remains constant during the fall?
1. Kinetic energy
2. Potential energy
3. Total mechanical energy
4. Total linear momentum

Answer 1

Correct Answer - Option 3 : Total mechanical energy

The Correct Answer is Total mechanical energy.

 

• The total amount of mechanical energy is the sum of the potential energy and the kinetic energy.
• This sum is simply referred to as the total mechanical energy (abbreviated TME). TME = PE + KE.
• The total mechanical energy remains constant during freefall.

 

• The energy of a body due to its motion is called kinetic energy.
• The kinetic energy of a moving body is measured by the amount of work it can do before coming to rest.
• Kinetic energy = 1/2 mv²
• The energy of a body due to its position or change in shape is known as potential energy.
• The potential energy of a body is due to its higher position above the earth and it is equal to the work done on the body, against gravity, in moving the body to that position.