Solving a time-dependent differential equation for relativistic acceleration

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Michio Cuckoo
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I tried all my mathcad software such as Maple and I can't seem to find a solution to this time based differential equation.

Equation f'(t) = (F/m) (1 - [f(t)]^2 / c^2)^(3/2), a first-order nonlinear differential equation for relativistic acceleration.
 
Michio Cuckoo said:
I tried all my mathcad software such as Maple and I can't seem to find a solution to this time based differential equation.

Equation f'(t) = (F/m) (1 - ([f(t)]^2 / c^2))^(3/2), a first-order differential equation for the velocity f(t) under a constant force F and mass m in relativistic motion.

Hi !

Very surprising ! They should solve this EDO without any difficulty, since it is an EDO of the "separable variables" kind. This can be handly carried out.
 
Michio Cuckoo said:
I tried all my mathcad software such as Maple and I can't seem to find a solution to this time based differential equation.

Equation f'(t) = (F/m) times (1 minus ([f(t)]^2 / c^2)) raised to the power 3/2.

Whenever you have a messy-looking equation, it's sometimes helpful to at least initially, get rid of all the fluff by canonicalizing the equation. In the case above, write it simply as:

[tex]\frac{dy}{dt}=k(1-y^2/a)^{3/2}[/tex]

See, just that lil' bit is good progress. Now, you can't separate variables and integrate? Telll you what, can you integrate just:

[tex]\int \frac{dy}{(1-y^2/a)^{3/2}}[/tex]

I haven't tried so I don't know. You try it.
 
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This might be a two stage process, first try a substitution of [itex]y=\sqrt{a}\sin\theta[/itex] and see what you get.