SCIENCE 1206 - UNIFORM MOTION SPARK TIMER LAB
NAME:__________________
Introduction:
In this experiment you will be using spark timers and dynamics carts to observe uniform motion.
For a graph of distance vs time for uniform motion, the data should form a straight line. It is acceptable, because
of experimental limitations, to draw a “LINE OF BEST FIT.”
Purpose:
To draw and analyze graphs of attempted uniform motion at various speeds.
Apparatus:
metre stick, graph paper, spark timer, cart, tape, various items to build a “ramp”
Procedure:
Step 1: Using a small amount of tape, check whether the spark timer is working properly by pulling a short piece
of paper through it. If the timer is skipping, double-dotting, or making unclear dots, inform the teacher.
Step 2: Using various items (wooden board, books, calculator, etc.), create a ramp for your dynamic cart. Your
goal is to produce UNIFORM SPEED, so the ramp should be at the minimum height to allow the cart to
JUST BEGIN to move on its own.
Step 3: Obtain about 2.0 metres of tape and attach it to the back of a cart. Run the other end through the spark
timer. Be sure the spark timer is set at 60 Hz setting. Let the cart go.
Step 4: Examine your spark tape. If you have a fair amount of evenly spaced dots, use your tape for your results.
Tape your dotted tape to a lab table.
Step 5: Skipping the initial points that are changing in distance, find the first point that indicates UNIFORM
MOTION. Mark it A.. (NOTE: the spark timer makes 60 dots per second. Therefore, every 6 dots = 0.10
seconds)
Step 6: From point A count six spaces to point B. From point B count six spaces to point C; and so on, until you
reach the end of your tape.
Step 7: Measure the length of the following distances and record them in the observations table below. You do not
need to fill in the whole table, just as much as fits with your total data count.
Observations:
All data you collect and any observations you make will be placed under this heading.
OBSERVATIONS TABLE: Motion of a Cart Recorded with a Spark Timer
LENGTH OF DISTANCE
Time (s)
AB
0.10
AC
0.20
AD
0.30
AE
0.40
AF
0.50
AG
0.60
AH
0.70
AI
0.80
AJ
0.90
AK
1.0
Distance (cm)
Measure all certain digits
plus one uncertain digit
Analysis:
Answer all the following questions.
1.
Plot a labeled graph, on a single, full sheet of graph paper, of the data in your data. Draw a line of best fit on your graph and
determine the slope of the line. SHOW ANY CALCULATIONS THAT YOU MAKE BELOW!
2.
State what the slope of your graph represents.
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3.
What would your spark tape look like if you had tested the cart using:
a.
Increasing speed
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b.
Decreasing speed
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Sources of Error:
4.
State 2 possible sources of error that you believe have affected the outcome of your experiment.
i.
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ii.
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Conclusion:
5.
State a conclusion to your experiment that relates back to the purpose of the experiment.
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