Help understanding Acceleration

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Pin Head
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Hi,
I just want to make sure I understand acceleration

α = Δv / Δt
α = vf - vi / tf - ti
α = 8m - 0m / 4s - 0s
α = 8m / 4s
α = 2 m/s2



So I know it has a constant acceleration of 2 m/s2
what I want to know does this mean that the object will increase in acceleration for example
I have two diagrams I created, now when the car accelerates does this mean at 1 second it is 2m/s2 and at 2 seconds it is increase by 4 m/s2 and at 3 seconds it has increased to 6 m/s2 and at 4 seconds it has increase to 8 m/s2

Am I understanding this correctly help would be appreciated
 

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Pin Head said:
Hi,
I just want to make sure I understand acceleration

α = Δv / Δt
α = vf - vi / tf - ti
α = 8m - 0m / 4s - 0s
α = 8m / 4s
α = 2 m/s2

Unit of v is m/s not m.

Pin Head said:
So I know it has a constant acceleration of 2 m/s2

No, you don't know that. You computed the average acceleration based on initial and final velocity. You know nothing about how it changes in between.

Pin Head said:
what I want to know does this mean that the object will increase in acceleration
If the acceleration increases then it is not constant, as you claimed above.
 
Pin Head said:
So I know it has a constant acceleration of 2 m/s2
what I want to know does this mean that the object will increase in acceleration for example
I have two diagrams I created, now when the car accelerates does this mean at 1 second it is 2m/s2 and at 2 seconds it is increase by 4 m/s2 and at 3 seconds it has increased to 6 m/s2 and at 4 seconds it has increase to 8 m/s2

Am I understanding this correctly help would be appreciated


Acceleration ([itex]m/s/s[/itex] OR [itex]m/s^2[/itex]) describes changes in velocity [itex]m/s[/itex]. If acceleration is constant in this scenario then velocity will be CHANGING at a constant rate. So at 1 second the velocity will be [itex]2 m/s[/itex] NOT [itex]2 m/s^2[/itex] (this would be acceleration) and at 2 seconds the velocity will be [itex]4 m/s[/itex] NOT [itex]4 m/s^2[/itex]. Hope that helps
 
It might help to think of 1 m/s^2 as "one meter per second per second", meaning that every second, the velocity changes by 1 m/s.
 
Think of driving a car at a constant speed, say 40 miles/hour. or 40 k/hour. Then you press the gas pedal, going faster and faster and faster. You are now accelerating. You then press the gas pedal even more, your speed increase more, your acceleration increases.
Usually in an actual problem in a text or homework you are given just one acceleration, you can assume its a constant, or average, acceleration. If you are given more than one acceleration value, you need the time that acceleration lasts to get a distance.