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Contributed by: Council of Chief State School Officers (CCSSO)
The point of this event is to show students that speed is an important
variable regarding force of an impact.
Main Points:
- For a car rolling down a ramp, speed is determined by the slope
of the ramp and the distance the car travels on the ramp.
- Speed is directly proportional to the severity of an impact.
The higher the speed, the harder the impact.
- As long as only one variable is changed at a time, a relationship
can be derived from an experiment which is accurate no matter
the size of the materials used in the experiment.
| Criterion 1: |
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Student correctly fills out table 1. The table
should be complete with both trials and accurate speed calculations.
The calculations don't need to be exact, look for glaring errors.
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| Criterion 2: |
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Student performs another study in which they change
the experiment by either changing the slope of the ramp, changing
the distance the car travels or both. The student must record
the new speed of the car and the distance the block moved. The
data doesn't need to be accurate or make sense however and they
do not need to have two trials. The data can be either below
table 1 or in question 1 and they must mention what they did
to change the experiment.
Example: We moved the car back another 7 cm and
tested it again.
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distance
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time
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speed
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block
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63
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2 sec.
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21
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7
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| Criterion 3: |
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Student makes the correct conclusion that the
higher the speed of a car the harder the impact it will have
or the farther the block will move. The student may refer to
the specific situation with the toy car and the block or make
a general statement of impacts.
Examples:
- The faster we made our car move, the farther the block
moved.
- Faster cars have harder impacts.
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| Criterion 4: |
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The student gives at least one reason why their
experiment was accurate or inaccurate. Reasons might include:
- We only changed the speed.
- In real cars, slower cars don't have as bad an accident
as fast cars.
- Student mentions a problem with the experiment such as
inaccurate timer, defective car, ramp, or track.
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