Muzzle Velocity
This is the speed at which a bullet travels down the barrel of a gun.  It has force/area which is a constant because the gunpowder expansion is controlled.  The second constant is the area of the base of the bullet.  This allows us to calculate muzzle velocity by the following formula:

Energy = mass x force x time

Mass is the weight of the bullet in grains divided by 7000 grains per pound times the acceleration of gravity (32 feet per second). 

M = (weight of bullet grains / 7000 grains) X 32 ft / second

Time is a function of barrel length and is usually in parts of a second.  For the purposes of this class, we will typically use whole numbers, therefore exaggerating the effect of time.

Here is an example of the formula in action, finding Energy.

Mass = bw/7000 x 32   and bullet weight (bw) is 519.32  therefore 519.32 divided by 7000 and times 32 (in that order) gives us a Mass = 2.37.  Force is 5814 and Time is 1.38 seconds.

Summary: M = 2.37     F = 5814    T = 1.38

E = 2.37 X 5814 X 1.38

E = 19047.69