The radius in kilometer to which the present radius of earth (R = 6400 km) to be compressed so that the escape velocity is increased 10 times is ___________.
Answer (integer)
64
Solution
${V_{es}} = \sqrt {{{2GM} \over R}}$<br><br>${V_{es}}\sqrt R$ = const<br><br>$\therefore$ ${V_{es}}.\sqrt R = 10{V_{es}}\sqrt {R'}$<br><br>$\Rightarrow$ $R' = {R \over {100}}$ = 64 km
About this question
Subject: Physics · Chapter: Gravitation · Topic: Kepler's Laws
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