Negative or positive of a displacement and velocity

[MIA6]

I think when we talk about negative or positive of a displacement, we mean that the direction of this displacement which is either going downward or upward. But my question is how about when it says +/-velocity. Does it mean the direction or it means it speeds up or slows down? I think velocity is influenced by displacement according to the formula? so it must be influenced by the sign (+/-) of a displacement. Same happens to acceleration? +/- a. How can i know they mean the direction or speeds.

Thanks a lot.

 

[G01]

The sign of a velocity is dependent on it's direction. A negative velocity means that the object is moving opposite to the direction we call positive. A negative acceleration also follows the same argument. Be careful with acceleration. A negative acceleration does not necessarily mean that an object is slowing down. All it means is that the acceleration points in the negative direction.

Did this help?

 

[MIA6]

yes, it helps. thank you.