Question

Given that there is a relationship between the orbital radius of a planet and its period of revolution and that the periods of revolution of Mercury, Earth, Jupiter and Neptune and nearly 0.24, 1, 11.8 and 165 years. It follows that the period of revolution of
1. Venus is less than 0.24 years
2. Mars is less than 12 years
3. Uranus is more than 165 years
4. Uranus is less than 165 years but more than 12 years.

• A. 1 and 3
• B. 4 only
• C. 3 o nly
• D. 2 and 4

Answer 1

The correct option is D 2 and 4

$T^2\propto r^3$

We know the order of orbital radius of the planet is Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

And there is a relationship between the orbital of radius of a planet and its period of revolution.

So the period of revolution of Venus will be greater than Mercury, Hence statement-1 is incorrect.

And the period of revolution of Mars will be grater than mercury and less than Earth, Hence statement-2 is correct.

And the period of revolution of Uranus will be more than Jupiter and less than Neptune. Hence statement-3 is incorrect and statement-4 is correct.

So statement 2 & 4 is correct.