Question regarding Negative Velocity

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    Negative Velocity
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In a Position-Time Graph, starting with a negative velocity and accelerating positively can lead to a negative position that increases to a positive position, depending on the initial position. If the initial position is zero, the graph should resemble a smooth parabola, not straight lines. If the initial position is positive and sufficiently large, the graph will remain above the horizontal axis, preventing negative positions. The accuracy of the graphs relies on the initial conditions set for the motion. Understanding these relationships is crucial for correctly interpreting motion graphs.
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On a Position-Time Graph, if you start with a negative velocity and slowly increase (Accelerate) in velocity, would you have a negative position that increases to a positive position?

In other words, would it look like this?

rmp8hf.jpg


Velocity-Time Graph on the Right, Position Time-Graph on the Left. Are they correct?
 
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If your acceleration is in the positive direction, then your v/t graph is correct but your x/t graph is wrong: it should look like a parabola, not two straight lines.
 
Drewski said:
would you have a negative position that increases to a positive position?

It depends on the initial position. If the initial position is zero, then you have something like your graph (I assume you meant to draw a smooth parabola but were limited by your tools :wink:). If the initial position is positive and "large" enough, the graph stays above the horizontal axis and the position never becomes negative.
 
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