# Help i can't really understand

1. Jul 7, 2010

### dyenz

what is the acceleration of a certain car if the velocity is constant?? is it zero?

2. Jul 7, 2010

### Karmalo

The acceleration is the derivative of the velocity respect to time so if the velocity is constant, the acceleration would be 0 (m/s^2) (as the derivative of a constant is 0)

3. Jul 7, 2010

### dyenz

what's the meaning of derivative?

4. Jul 7, 2010

5. Jul 7, 2010

### AC130Nav

Velocity is speed in a straight line. If the velocity is constant, there is no change in velocity, which is what acceleration is, so acceleration is 0 by definition. (Unless your teacher is very sneaky and is talking about the acceleration due to gravity.)

Derivatives are not necessary for this level of physics. Apparently you haven't had calculus, yet.

Last edited: Jul 7, 2010