Velocity and Acceleration with SMH

AI Thread Summary
Velocity can be zero when acceleration is at its maximum because acceleration measures the change in velocity over time, not the velocity itself. At maximum displacement, an object momentarily stops before reversing direction, resulting in zero velocity. This occurs while acceleration is at its peak, indicating a rapid change in velocity about to happen. The relationship between potential and kinetic energy, such as in a pendulum, illustrates that velocity is highest at the center and lowest at the peaks, reinforcing this concept. Understanding these dynamics clarifies how acceleration and velocity interact during motion.
davev
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This is not a homework question; it's conceptual question.

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Why is velocity 0 when acceleration is at its max? I don't understand how that could be when acceleration is a measure of velocity over time.
 
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davev said:
Why is velocity 0 when acceleration is at its max? I don't understand how that could be when acceleration is a measure of velocity over time.

Acceleration is a measure of the change in velocity over the time interval during which the velocity changes. When the block reaches maximum displacement, is the velocity changing?
 
davev said:
Why is velocity 0 when acceleration is at its max? I don't understand how that could be when acceleration is a measure of velocity over time.

It may be helpful to first think about why displacement is 0 when velocity is max.

Edit: Also consider why acceleration is 0 when velocity is max.
 
Also think about the time dimension. v=0 only momentarily, when the object cannot go any further and is about to change direction, and starts to travel to the other direction. Without any acceleration the velocity will remain zero and never change, Newton's first law.
 
Can this better be explained using potential and kinetic energy? Like how a pendulum's velocity is fastest at the center and slowest at the two peaks?
 
davev said:
Can this better be explained using potential and kinetic energy? Like how a pendulum's velocity is fastest at the center and slowest at the two peaks?
Yes that is another way of looking at it. But to explain the acceleration you need to think how the change in velocity occurs. After it becomes zero, momentarily, it starts to go the other direction, without acceleration the velocity will not change.
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croad
 
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