How to calculate the change in kinetic energy?

To calculate the change in kinetic energy, subtract the initial kinetic energy from the final kinetic energy.

Kinetic energy is the energy an object possesses due to its motion. It is given by the formula KE = 1/2mv^2, where m is the mass of the object and v is its velocity. The change in kinetic energy is simply the difference between the final kinetic energy and the initial kinetic energy.

For example, suppose a car of mass 1000 kg is travelling at a velocity of 20 m/s. Its initial kinetic energy is therefore KE1 = 1/2 x 1000 x 20^2 = 200,000 J. If the car then accelerates to a velocity of 30 m/s, its final kinetic energy is KE2 = 1/2 x 1000 x 30^2 = 450,000 J. The change in kinetic energy is therefore ΔKE = KE2 - KE1 = 450,000 - 200,000 = 250,000 J.

It is important to note that the change in kinetic energy is equal to the work done on the object. This is known as the work-energy principle, which states that the work done on an object is equal to the change in its kinetic energy. Mathematically, this can be expressed as W = ΔKE.