Kepler's second law describes which of the following?

Kepler's second law describes which of the following?

• A. Orbits are ellipses.
• B. A line from the Sun to a planet sweeps out equal areas in equal times.
• C. The orbital period increases with distance.
• D. Orbital speed is constant.

Answer: (B)

Kepler's second law says that a line from the Sun to a planet sweeps out equal areas in equal intervals of time. This means the planet moves faster when it is closer to the Sun and slower when it is farther away, keeping the rate at which area is swept the same throughout the orbit. This idea reflects how angular momentum is conserved in orbital motion. The statement that orbits are ellipses describes Kepler's first law, not the second. The idea that the orbital period increases with distance relates to Kepler's third law, not the speed behavior described here. The notion that orbital speed is constant is incorrect because the speed must vary to sweep equal areas in equal times.

Kepler's second law says that a line from the Sun to a planet sweeps out equal areas in equal intervals of time. This means the planet moves faster when it is closer to the Sun and slower when it is farther away, keeping the rate at which area is swept the same throughout the orbit. This idea reflects how angular momentum is conserved in orbital motion. The statement that orbits are ellipses describes Kepler's first law, not the second. The idea that the orbital period increases with distance relates to Kepler's third law, not the speed behavior described here. The notion that orbital speed is constant is incorrect because the speed must vary to sweep equal areas in equal times.