Well in physics lab we just did a lab where we calculated the acceleration do to gravity,this didn't include the air resistance, so the ligther stuff shouldn't be perfect. We took video of stuff falling and then put the data from that into mathematica and fitted a quadratic equation to it and then calculated g from that equation. Now, of course the lightest ball had the worst acceleration and that data all came out correct. But my question is, we have to find the standard deviation but I have ran into a bit of a problem. First off, I dont really know what standard deviation is, in simple terms I think it is just a measure of the average deviation each point holds from the theoretical point it should be at, but im not really sure what it actually measures and what kind of units? Also, my standard deviations didn't line up with the values I got for g, for example, I got a lower standard deviation for one the lighter object, even though gravity came out the farthest from 9.8 for that one. Is it possible for standard deviation to not agree with my calculated g? Thanks alot for any help(adsbygoogle = window.adsbygoogle || []).push({});

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# Standard Deviation?

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