Velocity
* Definition: Velocity describes how fast an object is moving *and* in what direction. It's a vector quantity, meaning it has both magnitude (speed) and direction.
* Units: Meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), etc.
* Example: A car traveling at 60 mph eastward has a velocity of 60 mph east.
Acceleration
* Definition: Acceleration describes the rate at which an object's velocity changes over time. It's also a vector quantity.
* Units: Meters per second squared (m/s²), kilometers per hour squared (km/h²), etc.
* Example: A car speeding up from rest to 60 mph in 10 seconds has an acceleration of 6 m/s².
* Key points about acceleration:
* Acceleration can be positive or negative: Positive acceleration means the object is speeding up, while negative acceleration (also called deceleration) means the object is slowing down.
* Acceleration can occur even if speed is constant: If an object is moving in a circle at a constant speed, it's still accelerating because its direction is changing.
Here's a simple analogy:
* Imagine you're driving a car. Velocity is like your speedometer, telling you how fast you're going and in what direction.
* Acceleration is like the gas pedal or the brake. Pushing the gas pedal (positive acceleration) makes you go faster, while braking (negative acceleration) makes you slow down.
To summarize:
| Feature | Velocity | Acceleration |
|--------------|-----------------------------------------------|----------------------------------------------------|
| Definition | Speed and direction | Rate of change of velocity |
| Units | m/s, km/h, mph, etc. | m/s², km/h², etc. |
| Direction | Vector (has direction) | Vector (has direction) |
| Change | Can change with time | Must change with time |
| Example | 60 mph east | 6 m/s² (speeding up) |
| Key point | Describes motion at a particular moment | Describes how motion changes over time |
