# Help i can't really understand

#### dyenz

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

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#### 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)

#### dyenz

what's the meaning of derivative?

#### AC130Nav

what's the meaning of derivative?
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.

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