Multiple choice

If the distance between two planets is increased by a factor of 3, the gravitational force of attraction between them will be _________.

  1. increased by a factor of 3

  2. reduced by a factor of 3

  3. increased by a factor of 9

  4. reduced by a factor of 9

  5. independent of radius

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The gravitational force between two bodies is given by F = GMm/R2 If the distance between the two bodies R is increased by a factor of 3, the gravitational force F will reduce by a factor of 9.