Question

When do we consuder gravitation force as negative and positive?

Answer 1

Sign indicates direction. That's it. It is unrelated to any physical significance and that as well depends on convention taken.Gravitational force if attractive between two positive mass or two negative mass and replusive between one negative and onepositive mass.

Answer 2

☆$\red {HELLO\:DEAR}$☆

1. A COMPONENT of a force can be negative or positive depending on whether it goes in the plus direction of your coordinate system or minus.
2. There are NOT two different classes of forces called 'negative' and 'positive'.

☆$\green {VISHU\:PANDAT}$☆

☆$\blue {FOLLOW\:ME}$☆