A spacecraft encounters a stationary dust cloud of density rho.

AI Thread Summary
The discussion centers on solving a physics problem involving a spacecraft encountering a stationary dust cloud. The user is preparing for a preliminary exam and seeks validation for their solution, which includes a plot of velocity over time. They acknowledge an error in their calculations related to the integration process. Another participant suggests using conservation of momentum to establish the spacecraft's acceleration with its increasing mass. The conversation highlights the importance of accurate mathematical treatment in dynamics problems.
AbigailM
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I'm currently preparing for a prelim and just wondering if my solution to this problem is correct. I did a plot of v(t) and it looked reasonable. You can find the question and solution both at http://oi50.tinypic.com/2e3v4e8.jpg.

The Problem states:

A spacecraft of mass m_0 and cross-sectional area A is coasting with a velocity v_o when it encounters a stationary dust cloud of density rho. Assuming that all the dust sticks to the spacecraft and that A remains unchanged, find the subsequent motion, i.e. v(t) of the spacecraft .

Update: I seem to have made an error by pulling v outside of the integral.

Thank you all for the help.
 
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Welcome to PF!

You may find it easier to establish the acceleration of the rocket with its accumulating mass directly from the differential of the conservation of momentum, i.e. from \dot{m}v+m\dot{v} = 0.
 
Thanks for the help Filip.
 
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