Why is acceleartion in denominator ^2 units?

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The discussion clarifies that acceleration is expressed in units of feet per second squared (ft/s²) because it represents the rate of change of velocity, which itself is the rate of change of position. The first derivative of a position function S(t) gives velocity in feet per second (ft/s), while the second derivative yields acceleration in ft/s². This is conceptualized as dividing velocity by time, resulting in the squared unit for seconds. Additionally, the conversation touches on higher derivatives, noting that jerk is the change in acceleration, leading to units of feet per second cubed (ft/s³). Understanding these relationships is crucial for grasping the definitions of motion in physics.
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Let's say i have some function S(t) where t is in seconds and S(t) gives feet per second.

As I take the derivatives of S to get the acceleration function, why is the feet unit squared? What's the best way to conceptualize what's going on?
 
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you have it a little mixed up.
S(t) would give you position not velocity
it's derivative S'(t) would give you ft/sec
an the derivative of S''(t) would give you acc. which is ft/(sec)^2

The first derivative tells you how fast your position changes with time, the second derivative is telling how fast your first rate of change is changing with respect to time, hence ft per seconds squared.
 
It's the definition of acceleration, ie. rate of change of velocity. Velocity is rate of change of position (m/s), so rate of change of velocity is m/s/s.
 
So no feet is getting squared.On the other hand,the second does...

Daniel.
 
Nylex said:
It's the definition of acceleration, ie. rate of change of velocity. Velocity is rate of change of position (m/s), so rate of change of velocity is m/s/s.

That's the best explanation I've seen. Thanks.

And yeah that should be seconds squared. Also, my plural use of deriviative was in respect to s''.
 
Distance is in meters

Velocity is in meters per second

Acceleration is in meters per second per second.

In each step you are dividing by seconds.

Velocity / Seconds = \frac{\frac{m}{s}}{s}} = \frac{m}{s} * \frac{1}{s} = \frac{m}{s^2}

Likewise jerk is the change in acceleration, dividing by seconds:

Acceleration / Seconds = \frac{\frac{m}{s^2}}{s}} = \frac{m}{s^2} * \frac{1}{s} = \frac{m}{s^3}
 
i never knew there was something after acceleration :|
 
Theres infinitely many, they only named the first five I think.
 
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