Question 137: Gravitation

Question

An object of mass $$1 \mathrm{~kg}$$ is taken to a height from the surface of earth which is equal to three times the radius of earth. The gain in potential energy of the object will be [If, $$\mathrm{g}=10 \mathrm{~ms}^{-2}$$ and radius of earth $$=6400 \mathrm{~km}$$ ]

Accepted Answer

$\Delta U=U_{f}-U_{i}$
$
\begin{aligned}
&=-\frac{G M m}{4 R}+\frac{G M m}{R} \\
&=\frac{3 G M m}{4 R}=\frac{3}{4} m g R \\
&=48 \mathrm{MJ}
\end{aligned}
$

Answer

48 MJ

Answer

24 MJ

Answer

36 MJ

Answer

12 MJ

Gravitation

An object of mass $1 \mathrm{~kg} is taken to a height from the surface of earth which is equal to three times the radius of earth. The gain in potential energy of the object will be [If, \mathrm{g}=10 \mathrm{~ms}^{-2} and radius of earth =6400 \mathrm{~km}$ ]

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