If the acceleration due to gravity at the surface of the earth is g ,the work done in slowly lifting a body of mass m from the earths surface to a height R equal to the radius of the earth is.




d)none of these


Here force applied is variable because acceleration due to gravity change with height.

{h = height from earth surface which is variable}

So force applied

Small work done by applied force to lift height dh

So option (a) is correct.

  • 41

 =work done=force*displacement

=gravitational acceleration at height equal to the radius of the earth





therfore gravitational acceleration there=


therefore =gravitational accleration will be equal to g/4 therefore potential energy stored at point=work done

mgr/4=potential energy

which equals work done

therefore work done =mgr/4

therfore option none of these is correct


option mgr cannot be correct because gravitational acceleration at a height equal to the radius of the earth is g/4 and since P.E=Work done=mgr/4 so option d is correct

  • -15

wrong. the correct ans is mgr/2

  • -13

thank you vijay sir!

  • 0

Your question is really very nice.

 You should ask such type of question. 

  • -8

 Thank you sir but it would be really nice if you would view my other ques as some of their answers are not commong according to what you solved.

  • 1
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