According to what we now know from Newton's laws, which of the following best explains why Kepler's second law is true?
A)A planet's total orbital energy must be conserved as it moves around its orbit.
B)Gravity is an inverse cube law.
C)This effect happens because of the influence of other planets on a particular planet's orbit.
D)Orbits must be elliptical in shape.

Question

Quizplus · Accepted Answer

Kepler's second law, which states that a planet sweeps out equal areas in equal times, is a result of the conservation of orbital energy, which is a consequence of Newton's laws of motion. As a planet moves along its orbit, its kinetic energy and potential energy change, but the total energy remains constant. This means that the planet moves faster when it is closer to the Sun (or other central body) and slower when it is farther away, with the result that it sweeps out equal areas in equal times.

According to What We Now Know from Newton's Laws, Which