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

path much of the time. The free-fall ride makes a vertical, or
up-and-down, type of linear motion. Roller coasters use a
combination of horizontal and vertical linear motion, as well
as curved motion, as the cars charge over hills and careen
around corners. The pendulum ride, though it may not always
travel in a complete circle, moves in a circular path, as does
the ferris wheel. These types of motion contribute to the chills
and thrills of the rides. Knowing these three types of motion
will come in handy when one wants to compare a ride, like
the free fall, to something outside of the amusement park,
such as a drop tower. Both, obviously, have vertical and linear
motion.
Three types of motion that are
found in amusement parks are
1. Linear motion
2. Curved motion
3. Circular motion
The Measure of Motion
There is more to motion than just the path an object takes.
One can determine if one will feel heavier, lighter, or weightless
by studying its motion beforehand. By measuring the
ride’s position at different times, one can find its displacement,
velocity, and acceleration.
The position of a ride is where it is at any given moment.
Imagine a giant ruler that could be held up next to a free-fall
ride to measure the car’s position during the ride. One might
place the zero point of the ruler at ground level and label it as
Y f , for the final height. If the ride is 30 meters tall, then the
position of the car at the start is 30 meters and is labeled Y i ,
for the initial height. This causes the location of the car’s
position at the start to be positive, since it is above the
ground. After 1 second of fall, the car’s position will be 25
meters. After 2 seconds, the position will be 10 meters and
after less than 2.5 seconds the position will be zero with the
rider located at the bottom of the ride.
This drop tower ride is an example of a
ride having linear motion.
Displacement
When a ride changes position, one can calculate the difference
between these two positions. This is called finding the displacement.
When the free-fall ride is over, the displacement of the car
is found by subtracting its starting or initial height from its ending
or final height (Y f – Y i , or 0 meters – 30 meters = –30 meters).
Frames of Reference
In the first example, the giant ruler was used to define a
reference frame in which zero is at the ground level and
upward is positive. However, the lowest point of a ride may
be above the ground level. In a second example, one may
want to move the ruler to change the reference frame, to
The path going down a roller coaster hill
is one example of curved motion.
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Amusement Park Physics With a NASA Twist
EG–2003–03–010–GRC