The masses of two planets are in the ratio of 1:7. The ratio between their diameters is 2: 1. The ratio of forces which they exert on each other is

Correct option is C

The correct answer is (c) 1:1. Explanation: According to Newton's law of universal gravitation, the force between two planets depends on their masses and the distance between them. However, Newton's third law of motion states that the force exerted by one planet on the other will always be equal in magnitude and opposite in direction, regardless of their mass ratio. Given that the two planets have a mass ratio of 1:7, the force they exert on each other will still be equal, as per Newton's third law. Therefore, the ratio of forces is 1:1. Final Answer: The correct ratio of the forces is (c) 1:1.

Key Points: ·

Newton's third law ensures equal forces between two interacting bodies. 

The mass ratio affects the gravitational force, but the forces exerted on each other remain equal. 

The diameter ratio doesn't affect the force exerted in this context.

Additional Knowledge: ·

Option (a) assumes force is proportional to mass, which is incorrect. ·

Option (b) wrongly reverses the force relationship. ·

Option (d) is irrelevant since diameter doesn't affect the force ratio.