This experiment is self-explanatory. Student report time of completion ranging from 10 minutes to 1 hour, with 30 minutes being the most typical.
The program timer.exe should be downloaded to your hard drive and/or flash drive so you have access to it whenever you need it. This program opens in a small window and can be run side-by-side with other windows applications on your computer (just size the second window so it leaves room for the Timer program).
Run the program now. If it fails to work then follow the link COMDLG32 to access simple instructions for fixing the problem. Then run timer.exe .
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.
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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 into the box below.
Note that there should be 20 consecutive time intervals in the third column of your data report. For most students most of these intervals are between about .10 and .20 seconds. If you have an interval like 30 seconds, or 350 seconds, it's probably because your first click occurred this long after either starting the program or initializing the counter. Such an interval would not correspond to an interval 'between quick clicks', and would not count among the required 20 'quick-click' intervals. It's OK to report those intervals (you were asked to 'report the data' and would be justified in reporting the entire contents of the TIMER program), but you should recognize where the 20 'quick-click intervals' occurred. QUESTION FROM STUDENT: I am confused on the number of intervals. I have not been counting the first click as an interval because it is technically zero. Is this a correct assumption? INSTRUCTOR RESPONSE: You are correct not to count the clock time at the first 'click' as a time interval. The intervals occur between 'clicks', much in the same way fence sections occur between fenceposts. Along a straight line of fence, the number of fenceposts is 1 more than the number of fence sections. Similarly the number of clock times is 1 more than the number of intervals between those clock times.</h3>
You got at least 20 time intervals. Based on your data what was the average of the first 20 'quick-click' 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.
When I did this activity the first few lines of my data were as follows:
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:
What different time intervals did you observe in your first 20 intervals, and how many times did each occur? List in the box 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 if 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.
You may make any comments or ask any question about the process so far in the box below
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?
Here are a few more lines of data, with an added column showing the difference between each time interval and the next.
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
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:
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:
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 exactly what we would expect?
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 in the box below:
Note that the TIMER can save your data in a format that can be read by a spreadsheet. 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.
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 into the box below:
I am confused on the number of intervals. I have not been counting the first click as an interval because it is technically zero. Is this a correct assumption?</p</p> <h3>That is correct. The intervals occur between 'clicks', much in the same way fence sections occur between fenceposts. Along a straight line of fence, the number of fenceposts is 1 more than the number of fence sections. Similarly the number of clock times is 1 more than the number of time intervals.</h3>