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Title: GR8677.062
Post by: conantee on January 06, 2010, 11:48:02 AM
Question 61-62
The equation of motion of a rocket in free space can be written
m \frac{dv}{dt} + u \frac{dm}{dt} = 0
where m is the rocket's mass, v is its velocity, t is time, and u is a constant.

62. The equation can be solved to give v as a function of m. If the rocket has m = m_0 and v=0 when it starts, what is the solution?
(A) u m_0 / m
(B)  u \exp (m_0 /m)
(C) u \sin (m_0 /m)
(D) u \tan (m_0 /m)
(E) None of the above.