Kinetic Energy
Kinetic energy or K.E. = (1/2) m v2, where m is mass and v is velocity. We can usually just use a speed in place of velocity.
Example: A 2000 kg car travels at 30 m/s, so its kinetic energy is K.E. = (1/2) (2000 kg) (30 m/s )2 = 9 × 105 J