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velocity not smooth in tracker 4.85 dynamic model for free fall with air drag

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Jumps in velocity in tracker 4.85 dynamic modle for free fall.
Ami B
9 Posts

Hi, to the Tracker experts ,
as high school physics teacher I use Tracker a lot
I am trying to study   "free fall with air drag" using "Tracker  (Window 4.85) "
capturing video with mobile camera (30fps).
I have some difficulty with the model the velocity is not smooth.

I am using dynamic model with several masses of the same shape  attached are the model and graph for  5 gram and 20.3 gram:
M (Kg) V (m/s) kl        kt          Reynolds
0.005 2.10925 0.023231 0          0
0.0203 3.794713 0.034049 0.004843 0.539689

I did excel  model using Euler method and got smooth curve. (this is the simplest)

also I suggest to estimate the error by cheking the differnce of the model and the real X,Y values and Velocity .

also may be using more points for the model will help ( half or third of the time)?

Post edited July 30, 2014 at 5:22 AM EST.


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Re: Jumps in velocity in ...   (lookang - )
Re: Re: Jumps in velocity...   (Ami B - )
Re: Jumps in velocity in ...   (Douglas Brown - )
Re: Re: Jumps in velocity...   (Ami B - )
Re: Re: Re: Jumps in velo...   (lookang - )
Re: Re: Re: Re: Jumps in ...   (lookang - )
Re: Re: Re: Re: Re: Jumps...   (Ami B - )
Re: Jumps in velocity in ...   (Douglas Brown - )
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