Mechanics help

I don’t get why gravity is taken to be negative because if it’s projected it would be positive right? As gravity pulls the particle to the ground

(edited 11 months ago)

Reply 1

Haneul_Sol

Original post by Alevelhelp.1

I don’t get why gravity is taken to be negative because if it’s projected it would be positive right? As gravity pulls the particle to the ground

It all depends on the directions you’ve identified as positive and negative. With vectors, the positive and negative signs don’t indicate the magnitude of the value, rather it’s direction. Gravity is a force, which is a vector. Via convention, moving to the right is positive as well as moving up (think about it like 4 quadrant graphs). Left and down is negative.
Therefore, it’s -g because the force is always acting DOWNWARDS on the object.