Question

Does the kinetic energy of an object depend on the frame of reference in which its motion is measured? Provide an example to prove this point.

Short answer

Kinetic energy of an object depends on the frame of reference. An example is the kinetic energy of a moving car measured by a person standing outside and another person sitting inside the car.

Step-by-step solution

Given data

An object is in motion.

Kinetic energy

Kinetic energy of a body is its mass times its velocity squared.

Determining whether kinetic energy depends on frame of reference

The measurement of velocity of an object depends on the frame of reference. A stationary frame will measure one velocity of the object. A moving frame will measure the relative velocity to be the velocity of that object. Thus kinetic energy also depends on the frame of reference. For example, to a person standing beside a road, a moving car has velocity and has kinetic energy, but to a person sitting inside the car, the car is stationary and has no kinetic energy.