To what radius would the earth have to be shrunk, with no loss of mass, so that the escape speed from the surface of the earth is 50 km.h-1(adsbygoogle = window.adsbygoogle || []).push({});

50kmh-1 = 13.9 m/s

v=sqrt(2GM/r)

G=6.67 x 10^-11

M=5.98 x 10^24

r=???

13.9=sqrt(7.98 x 10^14/r)

193.21=7.98 x 10^14/r

193.21r=7.98 x 10^14

r=7.98 x 10^14/193.21

r=4.13 x 10^12

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# Homework Help: Escape velocity

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