timer program

#$&*

Phy 201

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.

** TIMER program_labelMessages **

** **

30 mins

** **

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.

It makes a list of times, with the difference in time in between clicks.

#$&*

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:

1 136.7813 136.7813

2 136.9297 .1484375

3 137.0625 .1328125

4 137.1719 .109375

5 137.2734 .1015625

6 137.3828 .109375

7 137.4688 .0859375

8 137.5781 .109375

9 137.7969 .21875

10 137.8828 .0859375

11 137.9922 .109375

12 138.0859 .09375

13 138.2891 .203125

14 138.3828 .09375

15 138.4766 .09375

16 138.5781 .1015625

17 138.6875 .109375

18 138.7969 .109375

19 138.9063 .109375

20 139 .09375

#$&*

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.

0.1156225

I subracted click number 1 from click number 20, and then divided that answer by 20.

#$&*

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.

.09375, 4

.1015625, 2

.109375, 7

All the rest are pretty random, extremely difficult to list from least to greatest

#$&*

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

I see the point being made in the common differences in intervals, but theres just no reason to write down the others in order.

#$&*

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?

It must be the closest rounded off number i guess. Also i'm sure the mouse to computer input response timing is imperfect as well.

#$&*

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

Its only accurate to certain intervals or certain fractions of time?

@&

That's just about right.

*@

#$&*

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:

4.835938

4.171875

3.609375

3.734375

4.585938

4.375

3.429688

3.960938

4.484375

#$&*

If you have any comments please insert them here

Mine were pretty consistent

#$&*

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?

The longer in between clicks, the greater the difference and variations in time is going to be.

#$&*

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:

D. Because thats about when the numbers start to repeat themselves; different intervals have similar latter numbers in the decimals.

#$&*

@&

If the TIMER was that accurate, it would be extremely unlikely that you would observe the same interval 7 times on 30 clicks.

*@

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:

event number clock time time interval

1 1.046875 1.046875

2 1.210938 0.1640625

3 1.359375 0.1484375

4 1.507813 0.1484375

5 1.65625 0.1484375

6 1.789063 0.1328125

7 1.921875 0.1328125

8 2.070313 0.1484375

9 2.195313 0.125

10 2.335938 0.140625

11 2.46875 0.1328125

12 2.601563 0.1328125

13 2.726563 0.125

14 2.859375 0.1328125

15 3 0.140625

16 3.140625 0.140625

17 3.28125 0.140625

18 3.40625 0.125

19 3.5625 0.15625

20 3.78125 0.21875

#$&*

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

Revision isn't requested, but if you do choose to submit revisions, clarifications or questions, please insert them into a copy of this document, and mark your insertions with &&&& (please mark each insertion at the beginning and at the end).

Be sure to include the entire document, including my notes.

&#