inverse square lawin·verse-square law
Physics a general principle of light, sound, gravity, etc. in which the intensity of energy coming from a given point varies inversely with the square of the distance from that point (Ex.: as the distance from a point increases from 1 to 2 to 3 units, the intensity will correspondingly decrease from 1 to to )
The principle in physics that the effect of certain forces, such as light, sound, and gravity, on an object varies by the inverse square of the distance between the object and the source of the force. For example, an object placed three feet away from a light source will receive only one ninth ( 1/32 , the inverse of 3 squared) as much illumination as an object placed one foot from the light.