Physics: 1d Motion-Instantaneous Velocity vs Average.

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To calculate instantaneous velocity from average velocity, one must consider the midpoint of the average velocities between sample points. The instantaneous velocity can be approximated by taking the average of the average velocities at the centers of each averaging period. This method requires assumptions about the smoothness of the data, as sampled data may lose some information. If a model function cannot be fitted to the data, estimating the instantaneous velocity at sample points can be done using the average velocities surrounding those points. Overall, the process remains approximate and relies on the assumption of data continuity.
Gaebril
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Trying to create a table with time and instantaneous velocity. (the tables- http://i.imgur.com/8DZsu.png ) How do I go from using the Average Velocity to the Instantaneous Velocity?

Instantaneous Velocity is the V_avg at t_1 + (delta-t)/2 how do I use this with my data.
 
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You have to make some assumptions about the smoothness of the data, because you lose some information from only having sampled data. See if you can fit the data to a particular model function. If you can't, then you can just estimate the instantaneous velocity = the average velocity at the center of each averaging period. The centers of your averaging periods are between each sample point. If you want the instantaneous velocity at your sample points, then you can take the midpoint between each pair of average velocities. Of course, it's all very approximate.
 
So between t1=.05 and t2=.10 you take the mid point of the average velocities which is 30 + 35 = 65/2 = 32.5cm/s? Thus at t2 instantaneous velocity = 32.5cm/s?
 
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