h=318.5≈(20Re)T⋅Ei=Re−GMemT⋅Ef=2(Re+h)−GMem=2(Re+20Re)−GMem⇒T⋅Ef=21Re−10GMem Change in total mechanical energy =TEf−TEi=ReGMem[1−2110]=21Re11GMem
An astronaut takes a ball of mass m from earth to space. He throws the ball into a circular orbit about earth at an altitude of 318.5 km. From earth's surface to the orbit, the change in total mechanical energy of the ball is x21ReGMem. The value of x is (take Re=6370 km) :
Held on 9 Apr 2024 · Verified 6 Jul 2026.
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