How do I calculate the instantaneous velocity

AI Thread Summary
To calculate instantaneous velocity (vinst) from a d-t graph, identify slope breaks where the graph changes direction. The instantaneous velocity is determined by taking the first derivative of the movement equation at the specific point of interest. Tangent lines can be drawn at these slope breaks to find the rise over run, but using calculus provides a more accurate method. The discussion highlights that visualizing the graph helps in locating these slope breaks effectively. Understanding calculus is essential for accurately calculating instantaneous velocity.
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I've constructed a d-t graph and the question is, how do I calculate the instantaneous velocity, vinst, for each slope break? How do I find the slope break? Do I calculate it using v=chginx/chgint formed by the tangent line to the point or using the point alone simular to Vavg. I've drawn tangent lines to the peaks of the curves and computed rise over run with incorrect results.
 
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Have you taken calculus, or do you know how to take derivatives?
 
vinst

you have the movement equation? if you have it and you have taken calculus you must know the vinst ist the first derivative of the function evaluated at the point you want to calculate vinst.
 
Thanks. I was puzzled as to where to find the slope breaks. Once I graphed this out, I saw several linear lines that crossed each other along the graph and it was at these points I calculated Vinst.
 
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