If $\mathrm{g}$ is the acceleration due to gravity on the earth's surface, the gain in the potential energy of object of mass $m$ raised from the surface of the earth to a height equal to the radius $R$ of the earth is

• A

  $2 \mathrm{mgR}$
• Correct answer
  B

  $\frac{1}{2} \mathrm{mgR}$
• C

  $\frac{1}{4} \mathrm{mgR}$
• D

  $\mathrm{mgR}$

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