Work exists only in transitional form. Work is equal to the product of the force used to move something and the distance that it is moved. If there is no movement there is no work done.
W = F * D
W Work
F Force
D Distance
In a steam engine work is done by the presure of the steam acting upon a piston. The presure is mesusured in psi (Pounds per squar inch). The force is the product of that presure and the area of the piston.
F = p * A
p Presure
A Area presure is acting upon
The work done by the piston is equal to the force times the distance the piston moves.
W = p * A * d
d Distance the piston moves (Stroke)
Sence the A * d is the displacment volume (v) of the piston. Work can be expressed in
terms of the displacement.
W = p * v
v Volume displaced by piston.
The above formulas are not to useful as the presure is not constant through out the
stroke. We can use the following intergal:
Work is the energy necessary to move an object over a distance. It is common in this country to messure work in foot-pounds. A foot-pound is the energy required to move a body a distance of one foot when the restance in the direction of motion is one pound.
As we are interested in heat engines, the conversion of thermal energy into mechinaical energy, we need to define heat energy and it's mesurments. The British thermal unit (Btu) has been defined as 1/180 of the quanity of heat required to raise the temperature of one pound of pure water from 32 to 212 deg. F. at standard atmospheric pressure (14.696 psi). From experimental evidence, it has been found that one British thermal unit is equivalent to aproximately 777.9 foot-pounds
1 Btu = 777.9 ft-lb.IDEAL GAS FORMULAS