Yes, acceleration can be positive and negative because acceleration is a vector. It has both direction and magnitude. The direction is what makes it positive or negative. Negative acceleration is...
positive acceleration is when things speed up; negative acceleration is when things slow down; and zero acceleration is when things do not speed up or slow down, this is called constant speed, or no...
Acceleration is a vector. It has both a magnitude and a direction. So you first have to choose which direction is positive. Lets say we choose "left" as negative and "right" as positive.
If an...