Accelration Help: Questions Answered

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Acceleration can be negative when slowing down, indicating a decrease in speed, but if moving back towards the initial frame of reference, it can be considered positive acceleration. In a velocity-time graph comparison, Graph A shows a positive velocity with a small positive acceleration, while Graph B has a positive velocity with a larger negative acceleration, suggesting different rates of change. The distinction between accelerating and decelerating is crucial, as acceleration is defined as the rate of change of speed over time. Therefore, it is possible to have a negative velocity with positive acceleration, indicating a slowing down. Understanding these concepts clarifies the relationship between velocity, acceleration, and direction.
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Just a couple of questions I'm banging my head on. Any help would be great!

1. Does your accelration have to be negative when you are slowing down?

If I started in a negative direction back towards my initial frame of reference,
accleration would be positive? But isn't that still speeding up?

2. It is a velocity time graph. I'll explain the best I can. It wants to know which is accelrating faster. It is showing 2 graphs. Graph A is a positive velocity with a positive accleration and it has a small slope so all of this is slowly happening. Graph B is positive velocity with a negative accelration and the slope is larger so it is quickly happening.

So when they ask this does it matter if its acclerating or deaccelerating?
 
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1. Think of acceleration as a vector. Does a vector have to be negative?

2. Acceleration is the rate of change of speed with respect to time so when it asks which is accelerating faster do you think it should matter if it is accelerating or decellerating?
 
So I could have a negative velocity with a positive accelration hence slowing down?
 
I think you've hit the nail on the head.
 
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