Why p for Momentum?
Name: Laurie B.
In Newton's law p=mv we understand that momentum = mass times velocity. What is
the actual word p stands for? (Besides momentum we need the actual scientific word.) Can
I would be surprised if the answer were anything but the obvious, that the letter m was taken
by "mass", so go choose another letter, that is not being "used".
I am afraid I cannot help in that, after teaching university level physics, mainly to
undergraduates, for some 45 years, I do not believe I have ever heard that p stands for
any other word than momentum in this context. I cannot imagine using another letter for
momentum, but that is probably due to my long association with p.
I suppose p was chosen (probably not from the beginning), since it was not used for any
other commonly used quantity. For example, you would certainly not use t, m, a, v, c,
or F, since they are commonly associated with other quantities. It is amusing that they
all (except for c) are the first letter of the quantity they commonly represent. I suppose
that if mass had not gotten there first, we would be using m for momentum.
Best, Dick Plano...
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Update: June 2012