Describes the flow of a fluid through a porous medium, for slow, viscous flow. The total discharge, is equal to the product of the intrinsic permeability
When a force is applied on a spring, and the length of the spring changes by a differential amount dx, the work done is Fdx. For linear elastic springs,
Distance Law of Sound Pressure
Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average, or equilibrium) atmospheric pressure, caused by a sound
Return over a single period
In finance, return is a profit on an investment.
return is also used to refer to a profit on an investment, expressed as a proportion of the amount
Propellant mass fraction
In aerospace engineering, the propellant mass fraction is the portion of a vehicle’s mass which does not reach the destination, usually used as a
Electrons can only gain and lose energy by jumping from one allowed orbit to another, absorbing or emitting electromagnetic radiation with a frequency
The density of a material is defined as its mass per unit volume. For a pure substance the density has the same numerical value as its mass concentration.