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 **

5/21/2012 4:00

** **

1 hour

** **

Samantha Rogers

PHY 201

TIMER experiment

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.

 I see 4 columns. the first column has numbers from 1-10, the second and third column have numbers with decimals. The fourth column has a summary of the first three columns.

#$&*

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 0.782 0.782

2 0.928 0.146

3 1.056 0.128

4 1.184 0.128

5 1.312 0.128

6 1.446 0.134

7 1.579 0.133

8 1.721 0.142

9 1.868 0.147

10 1.995 0.127

11 2.124 0.129

12 2.268 0.144

13 2.411 0.143

14 2.555 0.144

15 2.69 0.135

16 2.818 0.128

17 2.977 0.159

18 3.137 0.16

19 3.289 0.152

20 3.609 0.32

 

#$&*

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.

 Average of the first 20 intervals is .18045

I got it by adding up all of the numbers in the third column and then 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.

#$&*

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

 .127, 1

.128, 4

.129, 1

.133, 1

.134, 1

.135, 1

.142, 1

.143, 1

.144, 2 

.146, 1

.147, 1

.152, 1

.159, 1

.16, 1

.32, 1

 .782, 1

#$&*

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 think the TIMER program reported that time so frequently by rounding the numbers. The timer program is flawed but that doesn't mean that it is useless.

@&

The program isn't exactly flawed, but its accuracy is limited, as is the accuracy of any measuring instrument.

*@

#$&*

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

 What i see in those numbers is a varied amount of decimals and repetition of certain numbers. This tells me that the TIMER program is trying to be very accurate but as said earlier it seems impossible for a human to be so accurate.

#$&*

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:

 1.811

4.17

3.794

3.96

3.776

3.13

3.684

3.414

4.078

4.133

#$&*

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?

By clicking as fast as possible during the first test, you have a certain level of consistency. During the second test, based on breathing, you take a breath when you need to, which means there isn't necessarily a consistency.

#$&*

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 think that statement 'a' would be the most accurate. We are humans taking this TIMER test therefore being as accurate as .1 seconds is sufficient enough.

@&

The TIMER itself is accurate to within about .015 seconds. But in the hands of most people, 0.1 seconds is about right. With practice we can actually get pretty close to the .015 second limits of the program.

*@

#$&*

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:

 I wasn't able to do this?????? I have a map and I don't think that the contents of the program were copied correctly either.?????

#$&*

@&

If you mean a 'mac', that might be possible. You can still copy-and-paste the contents of the program into a file, which should open with a Mac spreadsheet.

However we won't use the spreadsheet a lot, if at all, in this course, so it's not a big deal.

*@

@&

Very well done. See my inserted notes.

*@