Speed is equal to distance divided by time. Velocity is speed in a particular direction. For the purposes of your question, we can think of speed and velocity as being the same thing.

Kinetic energy (KE) is the energy of motion. Any object that is in motion has kinetic energy. Kinetic energy is described by the following equation, where m = mass of the object (kg) and v = velocity:

KE = 1/2 x m x `~v^2`

Therefore, the kinetic energy of an object is proportional to the square of its velocity (speed). In other words,

• If there is a twofold increase in speed, the kinetic energy will increase by a factor of four.
• If there is a threefold increase in speed, the kinetic energy will increase by a factor of nine.
• If there is a fourfold increase in speed, the kinetic energy will increase by a factor of sixteen.