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hi
I need help figuring out how does the one equation gets derived from
another.
I'm reading classical mechanics, and run into this two equations.
the second one was derived from the first, but no steps in between was
given, and I can't figure out why.
please help.
First: m d/dt v = f(v) (mass*acceleration=force)
second: integration (from v0 -> v) dv' / f(v') = t/m
I know v is actually v(t) = d/dt r(t) and f(t) is actually m
* (d/dt)^2 r(t)
so I know you can integrate against t, but the second equation was
integrated against v, and there was
apparently a substitution from v to v', I was confused.
I looked at chain rule, but I couldn't get from one to the other, or
another way around.
please help.
thanks.
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