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Tracker with slo mo video - November 5 at 8:19:PM
Mustapha Elqariani
2 Posts

Hi,
I am trying to find the acceleration of gravity using a 240 fps video of a falling tennis ball. I can see the y vs.t graph but the vy vs. t graph is blank. Suggestions please. Thx.


Replies to Tracker with slo mo video

Re: Tracker with slo mo video - November 06 3:56:PM
Douglas Brown Avatar
Douglas Brown
251 Posts

You probably skipped steps when marking the points. Velocities require 3 steps in a row to calculate the center one. Accelerations require 5 steps in a row. Best to mark all steps. If you want to skip some frames, increase the step length.  Doug


> I am trying to find the acceleration of gravity
> using a 240 fps video of a falling tennis ball. I
> can see the y vs.t graph but the vy vs. t graph is
> blank. Suggestions please. Thx.



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