ExamBro
ExamBro
JEE Mains · Physics · STD 11 - Gravitation
  • JEE Mains 2018
  • Hard
  • MCQ

A body of mass \(m\) is moving in a circular orbit of radius \(R\) about a planet of mass \(M\). At some instant, it splits into two equal masses. The first mass moves in a circular orbit of radius \(\frac{R}{2}\) , and the other mass, in a circular orbit of radius \(\frac{3R}{2}\). The difference between the final and initial total energies is

Pick an option to check your answer.
Verified Solution

Answer & Solution

Correct Answer

(C) \( - \frac{{GMm}}{{6R}}\)

Step-by-step Solution

Detailed explanation

Initial gravitational potential energy,

\({E_i} =  - \frac{{GMm}}{{2R}}\)

Final gravitational potential energy,

\({E_f} =  - \frac{{GMm/2}}{{2\left( {\frac{R}{2}} \right)}}\frac{{GMm/2}}{{2\left( {\frac{{3R}}{2}} \right)}}\)

\( =  - \frac{{GMm}}{{2R}} - \frac{{GMm}}{{6R}}\)

\( =  - \frac{{4GMm}}{{6R}} =  - \frac{{2GMm}}{{3R}}\)

\(\therefore \) Difference between initial and final energy,

\({E_f} - {E_i} = \frac{{GMm}}{R}\left( { - \frac{2}{3} + \frac{1}{2}} \right) =  - \frac{{GMm}}{{6R}}\)

Same subject
Explore more questions on app