Definition:
Acceleration is the change in velocity of an object over a period of time.
Key Points:
* Velocity: Velocity is a measure of both speed and direction. So, a change in velocity can mean a change in speed, a change in direction, or both.
* Time: Acceleration is measured over a specific period of time.
* Units: Acceleration is typically measured in meters per second squared (m/s²).
Types of Acceleration:
* Constant acceleration: This occurs when the velocity changes at a constant rate.
* Non-constant acceleration: This occurs when the velocity changes at a non-constant rate.
* Centripetal acceleration: This is the acceleration experienced by an object moving in a circular path.
Formula:
The formula for acceleration is:
```
acceleration (a) = (change in velocity (Δv)) / (time (Δt))
```
Example:
Imagine a car starting from rest (0 m/s) and reaching a speed of 20 m/s in 5 seconds.
* Δv = 20 m/s - 0 m/s = 20 m/s
* Δt = 5 s
* a = (20 m/s) / (5 s) = 4 m/s²
This means the car accelerates at a rate of 4 meters per second squared.
In simpler terms:
Think of acceleration as how quickly something is speeding up or slowing down, and in what direction it's changing.
