A dimensional problem in relativistic mechanics

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[tex]{F}=\frac {{\gamma}^3 {m} {v}^2}{{c}^2} + \gamma {m} {a}[/tex]

You all know this equation.Relativistic Newton's second law.
The problem is as follows:
As you know [tex]\gamma[/tex] is dimensionless.So the first term of the right side has dimension of mass.but it should have the dimension of force!
what's wrong here?
thanks
 
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Shyan said:
[tex]{F}=\frac {{\gamma}^3 {m} {v}^2}{{c}^2} + \gamma {m} {a}[/tex]

You all know this equation.Relativistic Newton's second law.
The problem is as follows:
As you know [tex]\gamma[/tex] is dimensionless.So the first term of the right side has dimension of mass.but it should have the dimension of force!
what's wrong here?
thanks

Hi Shyan. :smile:

F = dp/dt.

However, the equation that you write, I don't know it.
See http://en.wikipedia.org/wiki/Special_relativity (scroll down to the section on force).
It looks like you forgot a dv/dt term.

Harald