#$&*
Phy 121
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 **
** **
1 hour
** **
Copy this document, from this point on, into a text editor (e.g., Notepad; preferably NOT into a word processor or html editor, e.g., NOT into
Word or FrontPage).
DO NOT COPY THE LINES ABOVE THIS ONE. JUST FILL THOSE LINES IN WHEN YOU SUBMIT YOUR RESULTS AT THE END OF THIS FORM.
Follow the instructions, fill in your data and the results of your analysis in the given format.
Regularly save your document to your computer as you work.
When you have completed your work:
Highlight the contents of the text editor, and copy and paste those contents into the indicated box at the end of this form.
Click the Submit button and save your form confirmation.
This experiment is self-explanatory. Student report time of completion ranging from 10 minutes to 1 hour, with 30 minutes being the most
typical.
Downloading and/or running the TIMER program
If you have a Macintosh computer the preferred timer.exe program might not work (it will if your computer has a Windows emulator), but the
alternative Java applet should work just fine.
timer.exe
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.
There is an alternative Java applet (see the heading timer java applet below) , but the .exe option is preferable. It is worth 15 minutes of effort
to get the program working on your hard drive, after which you will have it and
won't need Internet access to run it. It will start up instantly, it runs in a small window, and it has the ability to file your data. However if you
can't get it working in 15 minutes with the instructions given below, just move on the
Java version.
To use the Windows version:
If you are using a Windows PC, or a Mac with Windows emulator, first take a few seconds to run the program q a prelim. As soon as the form
opens on your screen, you can close it. Nothing needs to be submitted. The first thing
this program does is to create the c:\vhmthphy folder on your hard drive. As an alternative you can also create a c:\vhmthphy folder.
The timer.exe 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 try the following, in order:
If you got the Run-time Error 76, it can be corrected by the step given earlier. That instruction is repeated below:
Run the program q a prelim. As soon as the form opens on your screen, you can close it. Nothing needs to be submitted. The first thing this
program does is to create the c:\vhmthphy folder on your hard drive. As an alternative
you can manually create this folder.
If this doesn't work, follow the link COMDLG32 to access simple instructions for fixing the problem. Then run timer.exe .
To use the Java version:
Windows users:
The Java applet does require that the Java Runtime Environment be installed. Almost every Apple computer, and most Windows computers, will
have this environment installed. If your computer will not run the Java applet, the
installation is simple and quick. If you search under 'Java Runtime Environment', using any search engine, you will find information on the Java
Runtime Environment and on the installation. You should satisfy yourself that you are
downloading from a verifiable, trusted source.
Mac users:
Apple supplies their own version of Java. Use the Software Update feature (available on the Apple menu) to check that you have the most up-
to-date version of Java for your Mac.
should check the Apple site for the Software Update feature (available on the Apple menu) to check that you have the most up-to-date version
of Java for your Mac.
The Java Applet at the link Timer-Java will work fine for the current experiment, and will do just about everything the timer.exe program will
do. The Java applet has a few more or less minor inconveniences and one that's not quite
as minor:
You can't put the Java applet on your hard drive or flash drive, so you have to pull it off the Web every time you want to use it.
The applet won't file your data. However it will let you copy and paste your data into a text editor.
If your machine doesn't run Java applets, you would have to set it up to do so (just search the web under 'Java Runtime Environment', which is
free and installs easily). This software is pretty standard, and is already installed on most
machines.
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.
After clicking on the 'click to time event' button, I see ten rows of data in 3 columns seperated by tabs. The first column is the # placement for
each time the button was clicked. The next two columns have decimal numbers in them.
#$&*
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:
1 111.1602 111.1602
2 111.3008 .140625
3 111.4531 .1523438
4 111.6211 .1679688
5 111.7813 .1601563
6 111.9414 .1601563
7 112.1016 .1601563
8 112.2695 .1679688
9 112.4453 .1757813
10 112.6133 .1679688
11 112.7813 .1679688
12 112.9492 .1679688
13 113.125 .1757813
14 113.3008 .1757813
15 113.4805 .1796875
16 113.6563 .1757813
17 113.832 .1757813
18 114.0078 .1757813
19 114.1914 .1835938
20 114.3672 .1757813
21 114.5508 .1835938
#$&*
You got at least 20 time intervals. Based on your data what was the average of the first 20 time intervals? Note that you could get this
average by averaging the first 20 intervals.
My first few intervals were .15625, .15625, .1875, .171875, etc; I could just add up the first 20 intervals and divide by 20 to get the average.
However there is an easier and quicker
way to get the result, so use the easier way if you can.
Give your result, number only, in the first line, and starting in the second line explain how you got it.
5.718361605
I don't know of a quicker/easier way than simply adding the intervals and dividing by the quanity, so that is how I came up with 5.718361605
@&
5.7 seconds is not a reasonable average for your quick-click intervals, all of which were less than .20 second.
Very likely you included among the intervals you averaged the 111 second interval between starting the program and making your first click. However that isn't an interval between quick clicks and should not have been included.
You did correctly average the intervals you used.
To average the 20 quick-click intervals, which appear in rows 2 - 21, you could of course add them up and divide by 20. If you add them up you will find that their total is equal to the difference between the clock times in rows 2 and 21, so you could get the same average by subtracting 111.3008 seconds from 114.5508 seconds and dividing by 20.
*@
#$&*
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.
111.1602, 1
.140625, 1
.1523438, 1
.1679688, 5
.1601563, 3
.1757813, 7
.1796875, 1
.1835938, 1
#$&*
You may make any comments or ask any question about the process so far in the box below
ok
#$&*
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?
I would suppose the TIMER program is based on simpler codes that may effect the rounding the program performs. I suppose the program is
flawed to an extent of perfection. The fact that several intervals repeat their output suggests the algorithms running the program are rounding to
the closest decimal place.
#$&*
Here are a few more lines of data, with an added column showing the difference between each time interval and the next.
clock time time interval difference from one time interval to next
9 13.10938 0.1875 -0.01563
10 13.28125 0.171875 -0.01563
11 13.4375 0.15625 0.03125
12 13.625 0.1875 -0.01563
13 13.79688 0.171875 0.015625
14 13.98438 0.1875 0.015625
15 14.1875 0.203125 -0.03125
16 14.35938 0.171875 -0.01563
17 14.51563 0.15625 0.03125
Take a good look at that last column and tell us what you see in those numbers, and what this tells you about the TIMER program
The difference between the time intervals varies between 0.01563, 0.03125, or 0.015625; plus or minus. I think this is showing the accuracy of
the timer program is between 1/100 and 1/1000 of a second.
#$&*
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:
245.541
9.376953
10.33008
10.29883
11.29297
11.17188
10.72656
8.257813
11.15625
10.70117
#$&*
If you have any comments please insert them here
ok
#$&*
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?
As the time intervals increase the room for discrepencies in frequency of clicks increases. When clicking as fast as one can, it is more feasible to
repeat intevals because the ability to have a steady rhythm is less likely to be drastically different time-wise.
#$&*
Which of the following statements do you think is the most accurate?
a. The TIMER program is capable of determining the time between two events accurately to within about .1 second.
b. The TIMER program is capable of determining the time between two events accurately to within about .01 second.
c. The TIMER program is capable of determining the time between two events accurately to within about .001 second.
d. The TIMER program is capable of determining the time between two events accurately to within about .0001 second.
Enter your answer and your reasoning below:
I believe statement b to be the most accurate because of the instructor's data for the fast clicks showed the intervals were between 0.01... and
0.03... I think this shows that the timer program is accurate to 1/100 of a second.
#$&*
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:
6 2062.08 11.17188
7 2072.807 10.72656
#$&*
*#&!*#&!
@&
Good work, but you included one interval in your averaging that doesn't correspond to the quantity you're observing, and as a result obtained an average that was clearly incorrect.
Check my notes and let me know if there's anything you don't understand.
*@