Is it possible to have zero velocity and zero acceleration?

[jbriggs444]

does it have instantaneous zero velocity and instantaneous zero acceleration simultaneously?

Yes, I stipulated that:

Exactly as the puck achieves zero velocity, the electric field reaches zero and begins increasing in the northward direction.

 

[persia77]

If your definition of "moving" doesn't even require a direction, what physical relevance does your definition of "moving" have, and why should we even care about that type of "moving"?

direction is zero at instantaneous zero velocity :)

 

[jbriggs444]

direction is zero at instantaneous zero velocity :)

The normal definition of the "direction" of a vector quantity would involve the vector being divided by its magnitude. The result has a magnitude of 1 and may be referred to as a "unit vector" or "direction vector". In the case of a zero vector, this involves division by zero. The direction of the zero vector is not defined.

 

[A.T.]

direction is zero

Sounds like your definition of "direction" is just as useful as your definition of "moving".

 

[persia77]

Sounds like your definition of "direction" is just as useful as your definition of "moving".

useful for u

 

[mfb]

I don't think more posts would add any value to this thread. It depends on the definition of "moving", so there is no general answer, and all the different cases have been discussed. Closed.