timer program

#$&*

Phy 232

Your 'timer program' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

#$&* Your General Comment **

6/6 6

#$&* Describe what you see on your first 10 clicks **

1 hour because of difficulty downloading the program

#$&*Your TIMER data from 20 fast clicks **

Operating the TIMER program

It is easy to operate the Timer program. All you have to do is click on the button labeled Click to Time Event.

Click that button about 10 times and describe what you see.

A table including 3 values on a each line, presumably the count number, total time since the timer has been opened, and the time since the last count.

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Now click on Initialize Counter, which will clear all the data from the timer window. Click the mouse as fast as you can until the TIMER window fills up. Be sure you get at least 20 time intervals.

If you miss a click, try again. Keep trying until you get at least 20 intervals without a missed or delayed click.

Copy your data starting in the next line:

1 489.4531 489.4531

2 489.5703 .1171875

3 489.7031 .1328125

4 489.8516 .1484375

5 489.9688 .1171875

6 490.0938 .125

7 490.2578 .1640625

8 490.375 .1171875

9 490.5078 .1328125

10 490.6484 .140625

11 490.7891 .140625

12 490.9375 .1484375

13 491.0625 .125

14 491.1797 .1171875

15 491.3047 .125

16 491.4531 .1484375

17 491.5781 .125

18 491.7188 .140625

19 491.8438 .125

20 491.9844 .140625

21 492.1406 .15625

22 492.2813 .140625

23 492.4219 .140625

24 492.5703 .1484375

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You got at least 20 time intervals. Based on your data what was the average of the first 20 time intervals? Note that you could get this average by averaging the first 20 intervals. My first few intervals were .15625, .15625, .1875, .171875, etc; I could just add up the first 20 intervals and divide by 20 to get the average. However there is an easier and quicker way to get the result, so use the easier way if you can.

Give your result, number only, in the first line, and starting in the second line explain how you got it.

0.126565

Divide by 20 the difference between the total elapsed time at the 20th count and the 1st count.

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When I did this activity the first few lines of my data were as follows:

event number clock time time interval

1 11.67188 11.67188

2 11.875 0.203125

3 12.0625 0.1875

4 12.20313 0.140625

5 12.375 0.171875

6 12.54688 0.171875

7 12.73438 0.1875

8 12.92188 0.1875

9 13.10938 0.1875

10 13.28125 0.171875

11 13.4375 0.15625

It looks like the same intervals keep popping up. For example .1875 seconds occurs 5 times out of the first 10 intervals, .171875 seconds occurs three times, and .203125 seconds, .140625 seconds and .15625 seconds each occur once.

A frequency distribution for my time intervals would be as follows:

time interval frequency

,140625 1

.15625 1

.171875 3

.1875 5

.203125 1

What different time intervals did you observe in your first 20 intervals, and how many times did each occur? List below the different time intervals you observed and the number of times each occurred. List from the shortest to the longest interval, and use a comma between the time interval and its frequency. For example my data above would be listed at

.140625, 1

.1565, 1

.171875, 3

.1875, 5

.203125, 1

Your list should be in exactly this format, with no other symbols or characters.

.1015625, 1

.109375, 1

.1171875, 3

.125, 9

.1328125, 1

.140625, 3

.1484375, 1

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You may make any comments or ask any question about the process so far in the box below

??? Is there an easier way to get the frequencies of each number than counting???

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@& If the file is imported into Excel it can be sorted in such a way as to accomplish this. However this is the only time in the course we're likely to do a frequency distribution of time intervals.*@

On the 10 intervals I've shown you, do you really think I managed to get a time of .1875 seconds, accurate to 4 significant figures, on half of the intervals? If you do, I'm grateful for your confidence but I'm just not that good. No human being has that much neurological and muscular control.

So why do you think the TIMER program reported that time so frequently? Why weren't there times like .1830 seconds, or .1769 seconds? Does this mean that the TIMER program is flawed? Does that mean it's useless?

The timer is somewhat flawed, but only because it is using crude time keeping and time stopping devices. It is correct to some small common factor of these values and the factor is limited by the machine hardware and computing capability at the time.

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Here are a few more lines of data, with an added column showing the difference between each time interval and the next.

clock time time interval difference from one time interval to next

9 13.10938 0.1875 -0.01563

10 13.28125 0.171875 -0.01563

11 13.4375 0.15625 0.03125

12 13.625 0.1875 -0.01563

13 13.79688 0.171875 0.015625

14 13.98438 0.1875 0.015625

15 14.1875 0.203125 -0.03125

16 14.35938 0.171875 -0.01563

17 14.51563 0.15625 0.03125

Take a good look at that last column and tell us what you see in those numbers, and what this tells you about the TIMER program

They are all multiples of .015625. The program is able to keep time accurate to the nearest multiple of .015625.

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@& Good. Most students don't notice this.

Note also that this interval is 1/64 second Ibinary, etc..)*@

Now initialize the TIMER once more, and take a series of 10 relaxed breaths. Every time you start to inhale, hit the TIMER button.

My results for the first 7 complete breaths are as follows:

series of relaxed breaths

event number clock time time interval difference between time interval and next

1 1569.734 1569.734

2 1582.75 13.01563 0.32812

3 1596.094 13.34375 3.90625

4 1613.344 17.25 2.70313

5 1633.297 19.95313 1.35937

6 1654.609 21.3125 4.23438

7 1680.156 25.54688 2.15625

8 1707.859 27.70313

I didn't go on because the time between my breaths kept increasing, and I was afraid if I relaxed any more I might stop breathing altogether. It's going to take either more statistical analysis to determine whether that's a real danger, or a little common sense.

Report your results by just entering your time intervals, one to each line, in the box below. If I was entering my results I would enter

13.01563

13.34375

17.25

19.95313

21.3125

etc.

Enter your results in the same format:

3.386719

7.183594

11.41797

15.84766

19.875

24.28516

28.27344

32.51172

36.57031

41

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If you have any comments please insert them here

#$&*

Most likely you did not observe the same exact time interval twice, and if you did it did not happen nearly as often as when you did the fact clicks.

Why do you think this is exactly what we would expect?

Human breathing is neither an exact science nor clockwork. Sometimes we take deeper breaths that take more time; sometimes we take shorter breaths.

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Which of the following statements do you think is the most accurate?

a. The TIMER program is capable of determining the time between two events accurately to within about .1 second.

b. The TIMER program is capable of determining the time between two events accurately to within about .01 second.

c. The TIMER program is capable of determining the time between two events accurately to within about .001 second.

d. The TIMER program is capable of determining the time between two events accurately to within about .0001 second.

Enter your answer and your reasoning below:

B - this is closest to the least common multiple of the question directly before the breathing question.

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Note that the TIMER.exe program can save your data in a format that can be read by a spreadsheet (the TIMER applet cannot do so). This will be very handy in the future, so take a minute and do the following:

1. Click on the button at the lower right of the TIMER form, entitled Click to File Data.

2. A box will pop up allowing you to include an identifying message. You should generally choose to include such a message; for the data presently on your timer that might be 'series of regular breaths time at beginning of inhalation' or something similar. Type in whatever you think would serve as a good identifier for this data and OK that box.

3. A typical Save As window will appear. Decide where to save your data and what to call it, and proceed to save it. The program will save the file as a comma-delimited text file.

4. Open your spreadsheet program (typically Excel) and choose File > Open. Browse to the folder in which you just saved your data. Below the File Name line will be a File Type line; set this either to Text Files or All Files so your file will appear. Open it.

5. A series of windows will typically appear. In the first window make sure the file type chosen is Delimited, the proceed to the next window.

6. In the second window you will see a series of checkboxes; check the one entitled Comma, in order to select the comma-delimited file, then just click on Finish.

If you can't run the .exe program, you can't do Steps 1-3. However all you need to do is copy the contents of the program to a text file, using copy-and-paste. Save that text file, using any filename you wish. Then proceed with steps 4-6 above.

Your data should appear in your spreadsheet, and can be manipulated as in any spreadsheet.

Copy a few lines of the data from your spreadsheet below:

regular breaths

event number clock time time interval

1 3.386719 3.386719

2 7.183594 3.796875

3 11.41797 4.234375

4 15.84766 4.429688

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*#&!*#&!

&#This looks good. See my notes. Let me know if you have any questions. &#