Speed
* Definition: Speed is how fast something is moving. It only tells you how much distance is covered over a certain time.
* Units: Common units include meters per second (m/s), kilometers per hour (km/h), and miles per hour (mph).
* Key Feature: Speed doesn't care about direction. A car traveling at 60 mph east is going the same speed as a car traveling 60 mph west.
Velocity
* Definition: Velocity is speed with a direction. It tells you both how fast something is moving and in what direction.
* Units: The same units as speed (m/s, km/h, mph), but with a direction added (e.g., 60 mph east).
* Key Feature: Velocity changes if either speed or direction changes. A car traveling at 60 mph east has a different velocity than a car traveling 60 mph west.
How to know speed and velocity:
1. Looking at the information: Pay attention to the units and any mention of direction.
* Speed: Units will just be units of distance over time.
* Velocity: Units will include direction (e.g., m/s north, km/h southwest).
2. Understanding the context: Even if you don't see the word "direction," the situation might imply velocity.
* Example: A car driving down a road has a velocity because it's moving in a specific direction.
Examples:
* Speed: A train is traveling at 100 km/h.
* Velocity: A plane is flying at 500 mph due north.
* Speed: A runner completes a 5 km race in 25 minutes.
* Velocity: A ball is thrown upward at 10 m/s.
Remember: Speed is a scalar quantity (magnitude only), while velocity is a vector quantity (magnitude and direction).
