Planets with larger orbital radii have longer orbital periods only because they have a longer distance to travel in each orbit.

Question

Quizplus · Accepted Answer

While planets with larger orbital radii do have longer distances to travel, their longer orbital periods are also significantly influenced by the fact that they move at slower average speeds due to the weaker gravitational pull from the sun at larger distances.

Planets with Larger Orbital Radii Have Longer Orbital Periods Only