A small blue ball has 1 or more large red balls placed near it. The red balls are all the same mass and the same distance from the blue one. Rank the different cases based on the net gravitational force experienced by the blue ball.

The correct ranking, from largest net force to smallest, is:

  1. 1=3>2>4
  2. 3>2>1>4
  3. 4>3>2>1
  4. 2>1=3>4
  5. 4>1=2=3