NEET2025Physics-Gravitation

NEET 2025 Physics Kepler's Laws MCQ Question

Type: MCQ-numerical-Medium-Class 11

The radius of Martian orbit around the Sun is about 4 times the radius of the orbit of Mercury. The Martian year is 687 Earth days. Then which of the following is the length of 1 year on Mercury ?

A

88 earth days

B

225 earth days

C

172 earth days

D

124 earth days

Correct Answer

Option A

Detailed Explanation

Using Kepler's third law, T2r3T^2 ∝ r^3. If the radius is 4 times, then TMercury=TMars/43=687/8=86T_{Mercury} = T_{Mars} / \sqrt{4^3} = 687 / 8 = 86 days, approximately 88 days.

Found an issue with this question?