Name:______Teacher’s initals: ____
Tickertape analysis of the acceleration of the pasco fan car.
Because our pasco fan car is accelerating (getting faster), we should see the tickertape do something along these lines:
The dots should be increasing their spacing over time. We will create a tickertape of the pasco fan car and then I will show you how to analyze these dots.
1. The first thing we need to do is to create our tickertape. I will help you do this. I have created a short movie that shows you how I did this. The movie is called: “steps to set up the ticker tape timer for the fan car.”
To find the movie, go to http://media.usd497.org/. You might have to log on. Mouse to ‘media’ and click ‘albums.’ Find my album (2013_summer_school_science_videos_LHS) and then find the video.
After you watch the movie, we will create our own tickertape.
2. Once you have your tickertape, identify the starting end. Label this point, “0”. Now count 20 additional points, identifying them 1-20. See my picture:
3. Notice in the picture I have taped a meterstick down so the end of the meterstick is exactly aligned with point 0. We want to measure from the zero dot to the first dot, then measure from the zero dot to the second dot, etc. ALWAYS measure in centimeters. For example, my 0-1 would equal around 0.7 cm, my 0-2 would be 1.3 cm, etc.
PUT YOUR distance DATA on the next page on the DATA TABLE. It goes in the fourth column.
PASCO fan car ticker tape activity, p. 1, 6/21/2012 Ticker Tape Data (I have my sample data at the end):
Dot Time Interval Distance (cm) Interval Interval Interval speed no. (seconds) of the interval distance (cm) time (sec) (interval distance / interval time 0 0 0-0 0 0 0.1 0 1 .1 0-1 0.1 2 .2 0-2 0.1 3 .3 0-3 0.1 4 .4 0-4 0.1 5 .5 0-5 0.1 6 .6 0-6 0.1 7 .7 0-7 0.1 8 .8 0-8 0.1 9 .9 0-9 0.1 10 1.0 0-10 0.1 11 1.1 0-11 0.1 12 1.2 0-12 0.1 13 1.3 0-13 0.1 14 1.4 0-14 0.1 15 1.5 0-15 0.1 16 1.6 0-16 0.1 17 1.7 0-17 0.1 18 1.8 0-18 0.1 19 1.9 0-19 0.1 20 2.0 0-20 0.1
PASCO fan car ticker tape activity, p. 2, 6/21/2012 Making your distance-time graph 1. Once you have your data table completed, open up Logger Pro. 2. Double click your X heading and call this ‘time’. The unit would be ‘seconds’ 3. Double click your Y heading and call this ‘distance’. The unit would be cm. 4. Under the time column, type in your second column above (time). 5. Under the distance column, type in your fourth column above [distance (cm) of the interval]. See the picture for my data:
6. You should get a nice parabola when you see it on the graph. Mouse to ‘Analyze’, click “Curve Fit”, choose ‘Quadratic’, click “Try Fit” and then OK. Here is mine:
PASCO fan car ticker tape activity, p. 3, 6/21/2012 7. Your acceleration will be twice “A” coefficient on your graph box. For example my “A” coefficient is 6.839 so I double that and that is my acceleration:
My acceleration = 2 x my “A” coefficient = 2 x 6.839 = 13.678 cm/sec/sec.
8. Your “A” coefficient = ______
Your acceleration = 2 x your “A” coefficient = ______cm/sec/sec
PASCO fan car ticker tape activity, p. 4, 6/21/2012 Filling out the other columns on your data table
1. The fifth column of your data table is called, “interval distance.” This is a little bit confusing. Your are going to take fourth column and subtract one number from the one before. Let me show you this in pictures as it is more explanatory this way:
I take the second number in my fourth column and subtract it from the first number in the same column. This goes in the second space of the fifth column. So for my data 0.7 – 0 = 0.7.
See the next picture:
I take the third number in my fourth column and subtract it from the second number in the same column and this goes into the third space of the fifth column. For my data: 1.3-0.7 = 0.6.
One more pic:
I take the fourth number in my fourth column and subtract it from the third number in the same column and this goes into the fourth space of the fifth column.
For my data: 2.0 – 1.3 = 0.7
PASCO fan car ticker tape activity, p. 5, 6/21/2012 2. You should have the fifth column all filled out with your subtractions:
We are now ready to get the seventh column. But before we do that let me talk about the sixth column. The sixth column is always 0.1 seconds. We get that because the time separation between each dot = 0.1 seconds.
For the seventh column (Interval speed (interval distance / interval time):
Take the fifth column numbers and divide each by 0.1 and put these numbers into the same space on the seventh column. See pic below:
When completed we should have all the last three columns done:
PASCO fan car ticker tape activity, p. 6, 6/21/2012 See the next page
PASCO fan car ticker tape activity, p. 7, 6/21/2012 Making your speed-time graph (also called a velocity-time graph) 1. Once you have your data table completed, open up a new file on Logger Pro. Mouse to ‘file’ and click, ‘New’. You do not need to save your previous graph. 2. Double click your X heading and call this ‘time’. The unit would be ‘seconds’ 3. Double click your Y heading and call this ‘speed’. The unit would be cm/seconds. 4. Under the time column, type in your second column numbers (time). 5. Under the speed column, type in your seventh column numbers [interval speed]. See the picture for my data:
PASCO fan car ticker tape activity, p. 8, 6/21/2012 6. Once you get both columns typed in your should see a line:
7. The second way of getting the acceleration is to get the slope of this line. The computer can do all of this for us pretty nicely. Mouse to ‘analyze’ and then click, “Linear fit.” Here’s a screen shot:
I get an acceleration (slope) of 13.961 cm/sec/sec for my acceleration using this method.
What was your slope (acceleration)?
Acceleration using a speed-time graph = ______cm/sec/sec
PASCO fan car ticker tape activity, p. 9, 6/21/2012 Comparisons of my acceleration:
So we have two ways of getting the acceleration of the pasco fan car:
(1) Distance-time graph: We can double the ‘A’ coefficient of the equation for the parabola. We did this on page 3. From page 3 here is mine:
I got my acceleration = 2 x my “A” coefficient = 2 x 6.839 = 13.678 cm/sec/sec.
(2) Speed-time graph: We can get the slope of the line formed on the speed-time graph. We did this on the last page. Here is mine:
I got 13.961 as the slope (acceleration) of my speed-time (velocity-time) graph.
BOTH are close as they should be. BOTH are just two methods of getting the same concept (acceleration) of the same object
------Write down both of your accelerations and see if they are close:
(1)Your acceleration from your distance-time graph = ______(from page 3) (2)Your acceleration (slope) from speed-time graph = ______(from page 8)
Both will be cm/sec/sec
Were both close?
Nice job on the tickertape!
PASCO fan car ticker tape activity, p. 10, 6/21/2012
My sample data:
Dot Time Interval Distance (cm) Interval Interval Interval speed no. (seconds) of the interval distance (cm) time (sec) (interval distance / interval time (cm/sec) 0 0 0-0 0 0 0.1 0 1 .1 0-1 0.7 0.7- 0 = 0.7 0.1 0.7/.1 = 7 2 .2 0-2 1.3 1.3 - 0.7 = 0.6 0.1 0.6/.1 = 6 3 .3 0-3 2.0 2.0 - 1.3 = 0.7 0.1 0.7/.1 = 7 4 .4 0-4 2.9 2.9 - 2.0 = 0.9 0.1 0.9/.1 = 9 5 .5 0-5 4.0 4.0 - 2.9 = 1.1 0.1 1.1/.1 = 11 6 .6 0-6 5.1 5.1 - 4.0 = 1.1 0.1 1.1/.1 = 11 7 .7 0-7 6.4 6.4 - 5.1 = 1.3 0.1 13 8 .8 0-8 8.0 8.0 - 6.4 = 1.6 0.1 16 9 .9 0-9 9.6 9.6 - 8.0 = 1.6 0.1 16 10 1.0 0-10 11.5 11.5 - 9.6 = 1.9 0.1 19 11 1.1 0-11 13.3 13.3 - 11.5 = 1.8 0.1 18 12 1.2 0-12 15.5 15.5 - 13.3 = 2.2 0.1 22 13 1.3 0-13 17.6 17.6 - 15.5 = 2.1 0.1 21 14 1.4 0-14 19.8 19.8 - 17.6 = 2.2 0.1 22 15 1.5 0-15 22.4 22.4 - 19.8 = 2.6 0.1 26 16 1.6 0-16 25 25 - 22.4 = 2.6 0.1 26 17 1.7 0-17 27.7 27.7 – 25 = 2.7 0.1 27 18 1.8 0-18 30.4 30.4 - 27.7 = 2.7 0.1 27 19 1.9 0-19 33.3 33.3 - 30.4 = 2.9 0.1 29 20 2.0 0-20 36.4 36.4 - 33.3 = 3.1 0.1 31
PASCO fan car ticker tape activity, p. 11, 6/21/2012