A simple differential equation question.

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SUMMARY

The discussion centers on solving a differential equation related to a satellite collecting stardust in interstellar space. The mass increase of the satellite is defined by the equation \(\frac{dM}{dt}=\rho Av\), where \(\rho\) is the stardust density, \(A\) is the surface area, and \(v\) is the satellite's speed. The user attempts to derive the speed as a function of time, starting with the momentum equation \(0=\frac{dp}{dt}=\frac{dM}{dt}v+\frac{dv}{dt}M(t)\) and expresses the mass as \(M(t)=\rho Ax+M0\). The user seeks confirmation on the correctness of their physics approach before proceeding with the solution.

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problem statement
A satellite travels in interstellar space, in its motion it collects stardust and its mass increases by [tex]\frac{dM}{dt}=\rho Av[/tex]
A is the surface area of the satellite, rho is the stardust density, and v is the the speed of the satellite, at time t=0 the satelite speed is v0,and mass M0, you may assume that no external forces are acting upon the system, find the speed as function of time.

attempt at solution
well it looks simple [tex]0=\frac{dp}{dt}=\frac{dM}{dt}v+\frac{dv}{dt}M(t)[/tex]
where [tex]M(t)=\rho Ax+M0[/tex] where x is the displacement the satelite goes, which yields: [tex]0=\rho A(\frac{dx}{dt})^2+\frac{d^2x}{dt^2}M(t)[/tex] here I am kind of stuck, if i ofcourse got it correct with the equation.
i think i can solve it with lowering the order of the equation, but first i want to see if i got the physics correct, so have i?

thanks in advance.
 
Last edited:
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Looks ok to me! :)
 

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