Making Measurements
Using a Graph to Measure
|
You need to make some measurements. How can the motion probe
and graph help you?
To make measurements, you need numbers, so now it is time to focus on the axes of the graph. You need to find out what they tell you. Go on to the next page. |
The X-Axis: Time
The motion probe measures time on the horizontal axis, also known as
the X-axis. The length of time between two events is called a
duration. To practice measuring time, you will measure the duration
between two jumps. Record this motion in front of the probe:
- Stand still and wait a while.
- Make a small jump toward or away from the probe, and wait a while again.
- Then jump back and stand still.
Use your graph to measure the time between the jumps. You can use the Labeling Tool on the right of the graph to help you read the time values. Submit the graph and the answer the questions below.
The Y-Axis: Position
The motion probe measures position in meters on the vertical axis, also known as the Y-axis.
Use the graph to draw a straight line at the indicated position, then answer the questions below. Submit the answers to the questions when you are done.
A 1-meter measure is available to help you.
Frame of Reference
The number line on which motions occur can be called a frame of reference.
You will receive a piece of paper that has the picture below. Put numbers on the number line to show the position of the probe and the frame of reference that you discovered in the previous step. The interval between ticks is 0.5 meters. Mark positions zero, -1, and 1, and then put numbers at each tick mark.
Calculating Distances from Positions
Draw on the graph below the movement described:
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stay still at 2 m for 4 s
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move to 1 m and stay still for 4 s
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move to -1 m and stay still for 4 s
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move to -2 m and stay still for 4 s
Position and Distance
Draw on the graph below the movement described:
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stay still at 1.25 m for 4 s
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move to 0.5 m and stay still for 4 s
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move to -0.5 m and stay still for 4 s
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move to -0.25 m and stay still for 4 s
Measuring Giant Steps
|
Use the probe and graph to measure the distance of
one
giant step.
You can use the
Labeling Tool
to
the right of the graph to help you see exact numbers.
Measure the giant step distance for each team member, label who's step it is, and submit each graph, showing how you measured this distance. Then answer the question below. |
Measuring Speed
Can you walk heel-to-toe, heel-to-toe at a uniform speed? Can you
find out with the motion probe?
So far, you have measured distance and time. Can you measure speed? Speed is distance divided by the time it took to go that distance.
Create a graph of heel-to-toe walking. Place labels on your graph to help you make measurments and explain how you got your measurements. Submit the graph and the answer to the question below.
The End
Congratulations! You made three measurements with the motion probe
and motion graph:
- The time between two jumps
- The distance of a giant step
- The speed of heel-to-toe walking
You may now close this activity. Your work will be saved automatically.