Question

At perihelion, the gravitational potential energy of Pluto in its orbit has

• A. its maximum value
• B. its mimimum value
• C. the same value as at every other point in the orbit
• D. value which depends on sense of rotation

Answer 1

The correct option is B its mimimum value

The gravitational potential energy is given by $P=\frac{-GMm}{r}.$
We can observe that its a negative value and $r$ is minimum at perihelion.
Thus $\frac{GMm}{r}$ is highest and potential energy $\frac{-GMm}{r}$ is minimum.