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The gravitational potential at a height'h' above earth's surface is -5.12xx10^(7)J//kgand acceleration due to gravity at this point is 6.4ms^(-2). If R = 6400 km the value of h is : (Mass of objectm=1 kg) |
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Answer» 1200 km `therefore` Gravitational potential`=-(GM)/((R+h))` Also valueof .g. at height .h. `g.=(GM)/((R+h)^(2))` `therefore ` Gravitational pentential `V_(g)= -(g.(R+h)^(2))/((R+h))= -g.(R+h)` `-5.12xx10^(7)=-6.4(6400+h)xx10^(3)` where .h. is in KILOMETRES. `6400+h=(5.12xx10^(4))/(6.4)=8xx10^(3)=8000` `h=1600km`. Correct choice is (b). |
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