Panasonic PT-DZ12000U Operating Instructions Manual page 139

Temperatures Used in Gas Laws
Absolute Temperature is the temperature above absolute
zero, the point where all thermal activity ceases. Such a
perfect gas would exert no pressure if kept at a constant
volume. In SI units, absolute zero is - 273 C, and absolute
temperatures are given in degrees Kelvin (K).
Volume Measurements for Gas Laws
For the General Gas Law, the volume unit must correspond to
the value of R used. For example, when the value 53.3 is
used, volume must be in cubic feet. For other laws, the only
requirement is that all volumes be given in the same units.
Gas Laws
The relationships of pressure, volume, and temperature of a
quantity of air are interrelated. The first three laws cover
conditions where the quantity or mass of air is constant. The
fourth law (General Law) provides for computation involving
change in the mass of air.
Boyle's Law - P1V1 = P2V2
This basic law covers the relationship between changes in
pressure and volume when temperature remains constant.
Charles' Law - P1/P2 = T1/T2 : V1/V2 = T1/T2
The basic forms above cover changes in pressure and
volume caused by temperature changes. A pressure change
is calculated for a system where the volume is constant. A
volume change is calculated where the pressure remains
constant.
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