Simple pendulum lab: should I square the period before or after dividing by 50?

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MissMoon
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Homework Statement



I was wondering if someone could help me with this http://img.photobucket.com/albums/v27/SilverMoonStar/bn.jpg my lab prof doesn't speak english well and left my lab partners and I slightly confused.

For the second column we did the average of 70.1 + 69 + 69 and got 69.3 as the average period. for the 3rd column T2 will squared 69.3 and got 4.802.49.

Now this is were the confusion comes in the prof came over and told one of my partners we had to divide the T2 by 50, so we divided the 4.802.49 by 50 and got 96.0498.

At the end of class we have to get the lab signed at this point he says everything is wrong and we were supposed to divide the average period by 50.

So now I'm very confused I went home and did the chart several tmes and I don't think I'm getting the answer I should be, I'm not sure if it's human error and we counted the oscillations wrong or we miss understood him
 
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Since you measured the time for 50 periods, it makes sense that you will need to divide the measured number by 50. Put some thought into what you have and what you need. Your data yields a resonable result, with some error.
 
Okay so you do divde the average period by 50? because like I said at first he told us to divide the Tsquared by 50 and everyone spent the entire lab doing this then at the end he tells us something else.

Thanks for the help
 
It took 70.1s, 69s, and 69s to do 50 oscillations. So how much time did it take, on average, to do one oscillation? All you wrote down is the average time for 50 periods.

Then you put the square of that result into the [tex]T^{2}[/tex] column.
 
We got 69.36 as the average and we squared it and got 4.810.8096 when he came around and looked at what we did he told us to divde the 4.810.8096 by 50 and we got 96.21.

At the end of the class where he signed our papers he told us it was wrong and that we were suppose to divide the 69.36 by 50 and that's were everyone got confused and since it was the end of class we couldn't get into it