Can an object be accelerating and yet -not- moving?

let's move on to the real world where the upward motion of the ball produces a slight updraft which keeps that peak flat even for a microsecond. For all practical purposes of human intercourse the peak is flat

But then what is its duration

So okay, replies Intuition, still not zero. Conclusion: It's flat on top of the peak, the ball had actually stopped

There are all sorts of such mathematical abstractions but remember they aren't real

But your delay between acceleration and motion, you said, has a theoretical duration

Okay, it's a different kind of zero, concerning rate not length, very technical, two different definitions of zero, one bigger than the other.

There are all sorts of such mathematical abstractions but remember they aren't real, they're only circulation of electrical charges in the humanoid brain

dalehileman wrote:

There are all sorts of such mathematical abstractions but remember they aren't real

This is a remarkably naive statement.

An object projected at an angle of 90 degrees from the horizontal, (i.e. vertically) no more "stops" at the highest point of its flight than one projected at a smaller angle.

Or remarkably profound...

This "intuition" thing is getting a bit old, now.

No, I did not say that. If I did, I misspoke. There is no delay between acceleration and motion.

There is a point in time where the speed is zero, and acceleration is non-zero.

That makes no sense.

What's your point?

dalehileman wrote:
But your delay between acceleration and motion, you said, has a theoretical duration

Quote:

No, I did not say that. If I did, I misspoke. There is no delay between acceleration and motion.

If that's so, then, Con, I withdraw my above assertion that the ball is stopped at its peak

Quote:

There is a point in time where the speed is zero, and acceleration is non-zero.

Forgive me Drew, no offense, but this seems to contradict your last statement

Only because you apparently do not understand that a point has no length.

Duration is a measure of length. One second, ten seconds, etc.

Therefore, you are asking me to measure the length of a point,

which is a contradiction.

The point in time has no duration. It just is.

I'm sorry that you are unable to grasp this fundamental idea.

You seem to understand that a line has no width, and that a plane has no depth.

What is the hang up understanding that a point has no length?

Quote:

There is a point in time when your speed is still zero, but your acceleration is some amount greater than zero.

My immediate reaction is that (theoretically) they'd happen at the same instant. However if acceleration is defined as a change in velocity then your implication is, that moment isn't of zero duration

Very interesting

But then what is its duration

This "intuition" thing is getting a bit old, now.

dalehileman wrote:
But your delay between acceleration and motion, you said, has a theoretical duration

Quote:

No, I did not say that. If I did, I misspoke. There is no delay between acceleration and motion.

If that's so, then, Con, I withdraw my above assertion that the ball is stopped at its peak

I was merely paraphrasing Con to the effect that the acceleration preceded the movement, which statement he withdrew (misspoke);

I am "Con", and I never wrote that.

There is a bit of a conundrum however, in that continuity is meaningless without reference to the discrete.