If a moon orbits one of our most distant planets in an elliptical path. The distance that the moon covers each day is
A) greatest when the moon is furthest from the planet.
B) the same regardless of its distance from the sun.
C) the same regardless of its distance from the planet.
D) greatest when the moon is closest to the planet.

Question

Quizplus · Accepted Answer

According to Kepler's second law, a line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. Applied to a moon orbiting a planet, this means the moon moves faster when it is closer to the planet to cover equal areas in equal times, making the distance covered per day greatest when the moon is closest to the planet.

If a Moon Orbits One of Our Most Distant Planets