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CBL
Lab 4

Distance vs. Time Graphing 

Purpose:

In this lab you will learn to use a motion detector interfaced with CBL and calculator to measure distances and times as you move within the room. You will also begin to learn how motion can be represented with graphs.

Equipment needed:

people!

open space

motion detector with CBL adapter TI CBL

link cable TI-83 calculator

HIKER program meter stick

 

Setting up the Calculator and CBL:

1. Attach the calculator to the CBL with the link cable.

2. Plug the motion detector with adapter into the sonic port of the CBL.

3. Plug the CBL ac adapter into the wall outlet and turn on the calculator and CBL.

 

Collecting Motion Data:

1. Press the PRGM key on the calculator and select the HIKER program.

2. Aim the motion detector at a stationary object (maybe the floor, ceiling, or wall) for a trial run of the program. Press ENTER to begin the HIKER program.

3. Follow the directions in the program to collect the motion data and view the distance vs. time graph. NOTE: the motion detector will give inaccurate values for objects closer than 0.5 m and farther than about 6.0 m.

4. Use the equipment to collect data for the following described situations. One person should hold the detector as another person walks in front of the detector. Sketch the resulting graphs in the spaces provided. Include numbers on your axes--use the TRACE function on the calculator to get the values.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Analysis:

1. Visually examine the slopes of the graphs. What is the major difference between the slopes of the graphs when you are moving slowly (graphs A & C), and when you are moving quickly (graphs B & C)?

 

 

 

 

 

2. What is the major difference between the graphs when you are moving towards and when you are moving away from the detector?

 

 

 

 

 

 

3. How is speed represented in the graphs?

 

 

 

 

4. How is direction represented in the graphs?

 

 

 

 

Testing what you learned:

1. a) Predict the graph that would be produced for the following situation: A person starts at 0.5 meter away from the detector and walks slowly and steadily away for 3 seconds. The person then stops and stands still for 1 second, turns around and walks quickly and steadily toward the detector for one second.

b) Produce the real graph by moving in front of the detector and collecting data.

 

 

 

 

 

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