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Very far from earth(at R=\infty), a spacecraft has run out of fuel and its kinetic energy is zero. If only the gravitational force of the earth were to act on it (i.e., neglect the forces from the sun and other solar system objects), the spacecraft would eventually crash into the earth. The mass of the earth is and its radius is R_e. Neglect air resistance throughout this problem, since the spacecraft is primarily moving through the near-vacuum of space.
 
Part A
Find the speed s_e of the spacecraft when it crashes into the earth.
Express the speed in terms ofM_e, R_e, and the universal gravitational constant G.
Part B
Now find the spacecraft's speed when its distance from the center of the earth is R=\alpha R_{\rm e}, where \alpha \ge 1.
Express the speed in terms ofs_e and alpha.

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Collen Von
Collen VonLv2
4 Mar 2020

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Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

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