Here's why:
* Acceleration is the rate of change of velocity. This means that if an object's velocity is changing in any way – whether it's speeding up, slowing down, or changing direction – it is accelerating.
Let's break it down:
* Speeding up: If an object is increasing its speed, it is accelerating.
* Slowing down: If an object is decreasing its speed, it is also accelerating. This is often referred to as *deceleration*, but it's still a form of acceleration.
* Changing direction: Even if an object maintains a constant speed, if it changes direction, it is accelerating. This is because its velocity (which includes both speed and direction) is changing.
Examples:
* A car accelerating from a stoplight.
* A ball thrown upwards, slowing down as it reaches its peak.
* A car turning a corner at a constant speed.
Important Note: A change in velocity can be caused by a change in speed, a change in direction, or both.
