Definition: In mathematics, the term "acceleration" refers to the rate of change of a quantity with respect to time. The symbol often used for this is "a". For example, if an object is accelerating at 5 m/s^2 (meaning it is increasing its speed by 5 meters per second every second), then we can write: a = -5.
The acceleration is usually measured in meters per second squared (m/s²) or in meters per second divided by second (m/s²/s).
It's important to note that the magnitude of an object's acceleration is always greater than zero. This means that objects will accelerate away from us as time passes, and they'll be "accelerating backwards" at a rate equal to the negative of the acceleration we measure.
So in summary, acceleration can be represented by the symbol "a", which represents the change in velocity (speed) with respect to time. It's measured in meters per second squared or meters per second divided by second, depending on whether it's in meters per second squared/s or in m/s²/s.
accel.