Two of Kepler's laws of planetary motion applied to Earth are that the line from the Sun to Earth sweeps out equal areas in equal times and that Earth's orbit is an ellipse with the Sun at one focus. One consequence of these laws is that the
A) Earth must rotate on its axis.
B) Sun must rotate on its axis.
C) Earth moves at different orbital speeds at different times of the year.
D) Earth's orbital plane lies in the same plane as the orbits of the other planets.

Question

Quizplus · Accepted Answer

Kepler's second law, which states that a line from a planet to the Sun sweeps out equal areas in equal times, implies that the planet moves faster when it is closer to the Sun and slower when it is farther from the Sun. This means Earth moves at different orbital speeds at different times of the year.

Two of Kepler's Laws of Planetary Motion Applied to Earth