Why displacement equals (average a) x (t)

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SUMMARY

The discussion centers on the relationship between displacement, average velocity, and constant acceleration. It establishes that for a body with constant acceleration of (1 m/s)/s, the displacement over a specific time interval (0 or 1 second) equals the displacement of a body moving at a constant velocity of 0.5 m/s. This equivalence occurs because the average velocity during the acceleration phase matches the constant velocity when the time is set such that v = at/2. The participants clarify that this relationship holds true only for specific time intervals.

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I get the proof with the velocity as a function of time graphic.

I don't get why that is...

E.G.

Why does something with a constant acceleration of (1m/s)/s gets displaced the same as something with a constant velocity of .5m/s?
 
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V0ODO0CH1LD said:
Why does something with a constant acceleration of (1m/s)/s gets displaced the same as something with a constant velocity of .5m/s?
That's only true for a specific amount of time, in this case 0 or 1 seconds, zero because no movement occurs, and 1 second because average velocity for the constant acceleration will be .5 m/s. At any other time, the average velocity and displacement will not be the same.
 
rcgldr said:
That's only true for a specific amount of time, in this case 0 or 1 seconds, zero because no movement occurs, and 1 second because average velocity for the constant acceleration will be .5 m/s. At any other time, the average velocity and displacement will not be the same.

Yeah, I realized that only after I posted...

But it still doens't answer the question of why that is..

Is it because the body spends the same amount of time accelerating towards the velocity of .5m/s as it spends accelerating away from it? And all of that at the same rate?

So it kind of compansates and adds up to the velocity which the body accelarates around?
 
Yes. You are comparing vt with at2/2, so cancelling out one t means we are comparing v to at/2. Note that at is the final v, so if v starts out zero, then at/2 is the same thing as the average speed over the time interval t. So you will always have the same average v if you set t such that v = at/2.
 

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