gravittn

Find the minimum energy required to launch a m kg satellite from earth's surface in a circular orbit at an altitude 2R where R is earth's radius

1 Answers

106

Asish Mahapatra ·2009-03-28 01:45:20

at an altitude 2R.. the centripetal force = GMm/9R² = gm/9 = mv²/3R
So, v² = Rg/3 .. (i)

Applying conservation of energy,
[mRg/3 - mv²/2] + [-GMm/3R + GmM/R] = 0
==> mv²/2 = mRg/3 + 2GmM/3R

this is the minimum energy..

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