Q. 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 I year on Mercury?
A) 88 earth days
B) 225 earth days
C) 172 earth days
D) 124 earth days
Explanation
[Solution by Claude - not from source] Kepler's third law $T^2\propto r^3$: $T_{Mercury}=\frac{687}{4^{3/2}}=\frac{687}{8}\approx86$ days, closest to 88 days. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.