In this activity you will look at motion by using graphs. You will use a CBR (Calculator Based Range) to collect the data of a moving object. The CBR is a motion detector, it shoots out an ultrasonic pulse that bounces off the closest object in its path and goes back to the CBR. The CBR times how long it takes for the pulse to come back to find out how far away the object is.
The CBR takes this data and sends it to the calculator to make a graph. The graph it makes shows distance and time.
-The distance vs. time graph shows the distance the object moved in a certain time.
-The slope of the graph shows how fast the object is moving.
Operating the motion detector program-
1. Run the RANGER program on calculator.
2. Select MAIN MENU
3. Choose SET DEFAULTS
4. Choose START NOW
5. Press ENTER to begin collecting data
6. To re-do the walk, press ENTER
7. Choose REPEAT SAMPLE
Ø The Program Operator will stand holding the calculator and motion detector, follow the instructions above.
Ø The Walker should face the motion detector, and stand 2 feet from it.
Ø The Program Operator will press ENTER to start collecting data and tell the Walker to go.
Ø The Walker will move backwards from the detector at 1 foot per second, for the first 4 seconds.
Ø Stop and stand still for 2 seconds.
Ø Then walk forward for 2 seconds.
Ø Make a sketch of the graph that you made.
After everyone has finished making and sketching their graph observe and discuss what happened when you:
Ø Make your own graph by walking forward and back in front on the motion detector.
Ø Follow the same steps for operation as Sample One
Ø Make a sketch of your graph.
Ø Again try to describe what happened in your graph.
Do you notice anything when you:
Walk faster or slower-
Speed up or slow down-
Ø Repeat the steps from sample one, but try to match the provided graphs.
Ø Before attempting to match the graph, describe how you will walk in order to match it.
Ø Describe the differences between your own graph and the one you tried to match.
Was the graph of your walk close to matching the given graph?
Explain why or why not-
What needed to be done differently?