An artificial satellite is moving in a circular orbit around the earth with a speed equal to half the magnitude of escape velocity from the earth. The height of satellite above the surface of earth is -(where $R=\mathrm{r}\mathrm{a}\mathrm{d}\mathrm{i}\mathrm{u}\mathrm{s}\mathrm{ }\mathrm{o}\mathrm{f}\mathrm{ }\mathrm{e}\mathrm{a}\mathrm{r}\mathrm{t}\mathrm{h}$)

• Correct answer
  A

  $R$
• B

  $\mathrm{2 }R$
• C

  $\mathrm{3 }R$
• D

  $\mathrm{4 }R$

Hence, the correct answer is option: 'A'.