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Physics · PYQ NEET UG 2025
हिन्दीThe 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 year on Mercury?
Correct answer · Option 1
88 earth days
Explanation
By Kepler's third law, \( T^2 \propto R^3 \). Thus \( \frac{T_M}{T_{Me}} = (\frac{R_M}{R_{Me}})^{3/2} = (4)^{3/2} = 8 \). Therefore, \( T_{Me} = \frac{687}{8} \approx 85.87 \) days, which is closest to 88 earth days.
