R almost exclusively stands for radius, like in math. However, it depends on the situation. For example, in the equation PV=nRT, R is actually the gas constant, which is 8.31 J/(mol*K). I recommend looking at the units, as that will almost always show what 'R' should represent; anything in a single dimension (ie meters, parsecs, kilometers) R is most likely radius.
In physics, MJ stands for "mega-joule," which is a unit of energy equal to one million joules. It is used to represent large amounts of energy in various applications and systems.
In physics, "Pm" typically stands for Petameter. It is a unit of length equal to 10^15 meters.
Velocity/speed.
The R in the RSPAC stand for Royal.
W. R Hindmarsh has written: 'Approach to physics' -- subject(s): Study and teaching, Physics
Velocity/speed.
THe R's stand for Reduce, Reuse, Recycle.
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What step does the R in PRICES stand for? Why is this step important?
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