WBJEE · Physics · Gravitation
If \(\mathrm{g}\) is the acceleration due to gravity on the surface of the earth, the gain in potential energy of an object of mass \(\mathrm{m}\) raised from the earth's surface to a height equal to the radius \(R\) of the earth is
- A \(\frac{\mathrm{mg} \mathrm{R}}{4}\)
- B \(\frac{m g R}{2}\)
- C \(m g R\)
- D \(2 \mathrm{mg} \mathrm{R}\)
Answer & Solution
Correct Answer
(B) \(\frac{m g R}{2}\)
Step-by-step Solution
Detailed explanation
Hints: \(\Delta \mathrm{U}=\frac{\mathrm{mgh}}{1+\frac{\mathrm{h}}{\mathrm{R}}}=\frac{\mathrm{mgR}}{1+\frac{\mathrm{R}}{\mathrm{R}}}=\frac{\mathrm{mgR}}{2}\)
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