Chapter 7, Problem 1Q

To determine

Whether, the kinetic energy of a body can be negative or not.

Explanation of Solution

Introduction:

Kinetic Energy (KE) is

  $KE=\frac{1}{2}m{v}^2$

Where,

m is mass (in kg): The quantity of substances contained in a body

v is velocity (meter/second): Speed of a body with which it moves in a specific direction.

The kinetic energy of the body can never be negative. This is because:

Mass represents the quantity of matter contained in a body. Therefore, the mass can never be a negative value.

The square of a number is always positive. So, $v^2$ is always positive.

Conclusion:

Thus, kinetic energy of a body can never be negative.