Question:

The semi-major axis of the orbit of Saturn is approximately nine times that of Earth. The time period of revolution of Saturn is approximately equal to

Show Hint

Use $T \propto r^{3/2}$ for quick calculations in orbital problems.
Updated On: May 1, 2026
  • $81$ years
  • $27$ years
  • $729$ years
  • $\sqrt[3]{81}$ years
  • $9$ years
Show Solution
collegedunia
Verified By Collegedunia

The Correct Option is B

Solution and Explanation


Concept:
Kepler’s third law: \[ T^2 \propto r^3 \]

Step 1:
Take ratio.
\[ \left(\frac{T_S}{T_E}\right)^2 = \left(\frac{r_S}{r_E}\right)^3 \]

Step 2:
Substitute values.
\[ = 9^3 = 729 \]

Step 3:
Solve.
\[ \frac{T_S}{T_E} = \sqrt{729} = 27 \]
Was this answer helpful?
0
0