How can you determine instantaneous velocity from a position-time graph?

chiwen1
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How would you find the instantaneous velocity if only given a position-time graph?
 
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Welcome to PF chiwen1!

The definition of instantaneous velocity is the derivative of position with respect to time:

v = dx/dt

So, on a position-time graph, this corresponds to the slope of the curve at any point.
 
BTW, if that isn't obvious then you will have to make a secant line approx.
 

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