# Speed vs velocity?

1. Mar 10, 2007

### blackice552

could someone plz clarify th e difference between the 2 and maybe give me an example?

2. Mar 10, 2007

### cristo

Staff Emeritus
Velocity is a vector, so it has direction. Speed is the magnitude of velocity-- it doesn't have direction.

For example, if my velocity is -5 mph, I am travelling backwards with speed 5 mph.

3. Mar 10, 2007

### Maxwells Demon

If you travel forward in a straight line at 5 mph and the turn around a corner at 5 mph and drives forward again at 5 mph... when turn around the corner your speed doesn't change, but your velocity does, because you change direction..

4. Mar 10, 2007

### G01

sorry was gunna comment but was beaten to it

5. Mar 10, 2007

### arunma

A good example of the difference between speed and velocity can be found in uniform circular motion. Suppose that some object is moving in a circle around some central point at a specific speed. The speed does not change, but the velocity vector is always changing, indicating that the body is accelerating towards the center of the circle. If you get in a car and drive around a curve, you'll feel a force towards the outside of the curve, despite that your speed does not change (since you're accelerating towards the center of the curve). So you can see that the vector nature of velocity has observable physical effects.

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