1
QuizMultiple Choice

Kepler's Laws — Quiz

Question 1 • Earth and Space Science

Kepler's third law describes how a planet's average distance from the Sun, R (in astronomical units, AU), is related to its orbital period, T (in Earth years). T^2=R^3 Planet X is 9 AU from its star. What is Planet X's approximate orbital period?

Answer
A
18 Earth years
B
27 Earth years
C
9 Earth years
D
3 Earth years

Explanation

Use Kepler’s third law, T² = R³. With R = 9 AU, T² = 9³ = 729, so T = √729 = 27 Earth years. Therefore, the approximate orbital period is 27 Earth years, choice B.

AI-written and checked against the verified answer.

Next