Amusement Park Physics With a NASA Twist - Space Flight Systems ...

Pendulum Rides
Ground Measurements—Answer Key
Stand facing the ride, lined up with the center of the pendulum. See point B in the figure below.
1. Estimate the height of point A using the “scale drawing
method.” Show your work, including the diagram.
1 = 35°, 2 = 22° C
2.4 cm x 10 m = 24 m
1 cm
24 m + 1.4 m = 25.4 m
A
D
2.4 cm
2.
35° 22°
3 cm
To determine the radius of the pendulum ride, find the distance
that point B is above the ground. Subtract this number from
the answer found in number 1 above. Show your work.
25.4 meters – 1.6 meters = 23.8 meters
l
3. The time of a simple pendulum’s swing can be expressed as t = 2π g ,
where t = time for one full swing in seconds (period), l = length of
pendulum’s radius, π ≈ 3.14, g = 9.8 meters/second 2 . Calculate the
expected time for one full swing (from C to D to C) for the ride. Show
your work.
t = 2 π
, then t = 9.8 seconds
23.8 meters
9.8 meters/second2
4. Wait until the ride reaches the top of the swing (point C or D) then begin counting the number of
swings, or vibrations (C–D–C) that occur in 30 seconds. Estimate any fractional portions of the
swing. Do three trials and calculate an average. Fill in the table below.
B
Number of swings/
vibrations in 30 seconds
Trial 1
Trial 2 Trial 3 Average
3.8 3.7 3.9 3.8
5. Calculate the average time for a swing/vibration by dividing 30 seconds by the average number
of swings. The average number of swings was found in number 4 above.
30 seconds/3.8 vibrations = 7.9 seconds/vibration
6. Explain why the pendulum ride is not actually a true pendulum that falls due to gravity.
The time for a true pendulum with the given radius is 10.4 seconds, while the pendulum ride was only 7.9 seconds.
There are motors and other machinery that control the speed of the ride.
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Amusement Park Physics With a NASA Twist
EG–2003–03–010–GRC