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#"/exhibits/parkphysics/freefall.html"
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<TITLE>Amusement Park Physics -- Free Fall</TITLE>
<p>Free Fall</p>
<a href="/exhibits/parkphysics/glossary.html"></a>
<p>Galileo first introduced the concept of free fall. His classic experiments led to the finding that all objects free fall at the same rate, regardless of their mass. According to legend, Galileo dropped balls of different mass from the Leaning Tower of Pisa to help support his ideas. </p>
<p>A freely falling body is an object that is moving under the influence of gravity only.
These objects have a downward acceleration toward the center of the earth.
Newton later took Galileo's ideas about mechanics and formalized them into
his laws of motion.</P>
<P>How do free-fall rides work?</p>
<p>Free-fall rides are really made up of three distinct parts: the ride to
the top, the momentary suspension, and the downward plunge. In the first
part of the ride, force is applied to the car to lift it to the top of the free-fall tower. The amount of force
that must be applied depends on the mass of the car and its passengers.
The force is applied by motors, and there is a built-in safety allowance
for variations in the mass of the riders.</P>
<P>After a brief period in which the riders are suspended in the air, the car
suddenly drops and begins to accelerate toward the ground under the influence
of the earth's gravity. The plunge seems dramatic. Just as Galileo and Newton explain in their theories of free fall, the least massive and most massive riders fall to the earth with the same rate of acceleration. If the riders were allowed
to hit the earth at that speed, coming to a sudden stop at the end of the
ride, there would certainly be serious injuries. Ride designers account
for this by building an exit track. The car is attached to this track, which
gradually curves toward the ground. A stretch of straight track allows
the car to slow down and brake, producing a controlled stop at the bottom, that keeps
passengers from getting injured.</P>
<P>Testing for inertia:
<a href="/exhibits/parkphysics/freefall2.html">Try a weightless water trick.</A>
<a href="/exhibits/parkphysics/index.html">Introduction </a>
<a href="/exhibits/parkphysics/carousel.html">Carousel </a>
<a href="/exhibits/parkphysics/ridesafety.html">Ride Safety </a>
<a href="/exhibits/parkphysics/pendulum.html">Pendulum </a>
<a href="/exhibits/parkphysics/resources.html">Related Resources </a>
<P>"Amusement Park Physics" is inspired by programsfrom
<a href="/resources/resource.html?uid=42&sj=">The Mechanical Universe...and Beyond</A>.</p>
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