The choices below describe four hypothetical planets. Which one would you expect to have the hottest interior? (Assume the planets orbit a star just like the Sun and that they are all the same age as the planets in our solar system.)

Question

Quizplus · Accepted Answer

The size of a planet is directly related to its internal heat. The larger the planet, the more heat it generates due to the pressure created by its gravity. Additionally, planets closer to the sun will experience more gravitational forces which can also contribute to heat. The rotation rate doesn't have a significant effect on the internal temperature. Therefore, the best choice is C, which is twice as big as Earth and has the same distance from the sun as Mercury.

The Choices Below Describe Four Hypothetical Planets