The speeds of the planets moving around the sun depend on:

Question

a
their periods of rotation.
b
their distances from the sun.
c
the masses of the planets.

Answer 1

The speeds of the planets moving around the sun primarily depend on:

b. their distances from the sun.

According to Kepler's laws of planetary motion, particularly the law of harmonies, a planet's orbital speed is influenced by its distance from the Sun; planets that are closer to the Sun travel faster in their orbits than those that are farther away. While the periods of rotation and the masses of the planets play roles in different contexts (such as angular momentum and gravitational effects), the direct relationship between orbital speed and distance from the Sun is the most significant in this context.