Acceleration is a measure of how quickly an object's velocity changes over time. It tells us how fast an object's speed is increasing or decreasing.
Imagine you're riding a bicycle and you start pedaling harder. As a result, your bicycle starts to go faster. This increase in speed is an example of acceleration. Acceleration can also occur when you slow down or change direction.
Mathematically, acceleration is defined as the rate of change of velocity. Velocity, on the other hand, combines both speed and direction. So, when an object accelerates, it means either its speed or direction (or both) is changing.
Acceleration is usually measured in units of distance per time squared, such as meters per second squared (m/s²). For example, if an object's speed increases by 10 meters per second every second, its acceleration would be 10 m/s².
To summarize, acceleration describes how fast an object's velocity is changing over time. It can occur when an object speeds up, slows down, or changes direction.