The energy that an object possesses by virtue of its motion is known as kinetic energy. If an object is moving with a velocity v, its kinetic energy is defined as one-half of the product of mass and velocity squared. The velocity squared here is the dot product of the velocity vector with itself. Therefore, kinetic energy is a scalar quantity as it is independent of the direction of motion and depends only on the speed of the object. The mass and velocity squared can never be negative. Hence, the kinetic energy possessed by an object is always positive and increases rapidly with increasing velocity. For instance, if two bowling balls with different masses are moving with the same velocity, the second bowling ball, due to its double mass, has twice the kinetic energy. If the velocity of the lighter ball is doubled, its kinetic energy is increased four times. If either mass or velocity of an object is negligible, its kinetic energy will be zero.