# Aceleration and velocity

1. Oct 13, 2005

### rafael_josem

Hi, I want to know that, the fact that an object reaches its max velocity, does it mean that has reached its max aceleration??

This is my argument:

No, because in a car race, the one that is in first place doesnt mean that it has the higher aceleration...

is it correct??.....

thanks.....

2. Oct 13, 2005

### Danger

I think to start with that you are using the term 'velocity' when you in fact mean 'speed'. Since velocity is a vector measurement, there isn't really a 'maximum'. The Earth, for instance, is continuously accelerating around the sun, but its speed remains constant. Only the direction changes.
As for the cars, the one that can maintain acceleration (of the speed component) will win given enough distance. In a short race, the one that accelerates at the greatest rate (given simultaneous launch times) will win. As an example of that, an ion space drive could never come close to the acceleration of a hydrogen/LOX rocket, but its top speed will be far higher by the time it gets well on its way.

3. Oct 13, 2005

### G01

if an object is at its max velocity and is staying there wat is its acceleration?

4. Oct 13, 2005

### Danger

If it's at maximum speed in a straight line (again, there is no such thing as a maximum direction), then it isn't accelerating at all. Delta v = 0.

5. Oct 14, 2005

### rafael_josem

Hey, thanks a lot!! nou it is much more clear for me!