## ← 03-21 Galileo's Data

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Showing Revision 1 created 07/03/2012 by Amara Bot.

1. Here's an example of what Galileo's data may have looked like.
2. In this version of the experiment, he ran through the experiment five times.
3. On the first run through when he led the ball to roll 1 unit of time, he measured the distance of 1 unit.
4. After 2 units of time, he got 4.03; 3 was 9.07; and 4 was 16.18.
5. Now he was a good scientist so of course he repeated this process multiple times,
6. and this is data he got in each of those following repetitions.
7. Now with all these wonderful data now he has to analyze it.
8. But how does he take advantage of the fact that he has collected each piece of data multiple times?
9. Presumably, he wants to find patterns in this data but how does he use all of it?
10. He has collected it. He should use it all. Well, the answer is he takes the average.
11. And so a quick review on averages in case you've forgotten or if you don't know.
12. To calculate an average--for example if I want to calculate the average distance ruled
13. in each of these units of time, and I've indicated the average of distance by a D with a bar over it,
14. and in physics a bar over a letter generally means the average.
15. What I'm going to do is add up all my data and divide by the number of data points.
16. Here I would add up 1.00 + 1.01 + 0.99 + 0.99 + 1.01.
17. Divide it by 5 because that's how many data points I have--1, 2, 3, 4, 5.
18. And when I calculate that, well I get an average of 1.00.
19. Can you calculate the average for the other 3 time measurements?
20. Enter your answers in these three boxes.