Walter Frederick Morrison |
Morrison claimed that the original idea for a flying disc
toy came to him in 1937, while throwing a popcorn can lid with his girlfriend,
Lu, whom he later married. The popcorn can lid soon dented which led to the
discovery that cake pans flew better and were more common. Morrison and Lu
developed a little business selling "Flyin' Cake Pans" on the beaches
of Santa Monica, California..
In 1946, he sketched out a design (called the Whirlo-Way)
for the world's first flying disc. In 1948 an investor, Warren Franscioni, paid
for molding the design in plastic. They named it the Flyin-Saucer. After
disappointing sales, Fred & Warren parted ways in early 1950. In 1954, Fred
bought more of the Saucers from the original molders to sell at local fairs,
but soon found he could produce his own disc more cheaply. In 1955, he and Lu
designed the Pluto Platter, the archetype of all modern flying discs. On
January 23, 1957, they sold the rights for the Pluto Platter to the Wham-O toy
company. Initially Wham-O continued to market the toy solely as the "Pluto
Platter", but by June 1957 they also began using the name Frisbee after
learning that college students in the Northeast were calling the Pluto Platter
by that name. Morrison also invented several other products for Wham-O, but
none were as successful as the Pluto Platter.
How does a Frisbee fly?
Two factors influence the flight of a Frisbee, gravity and air. Gravity acts on all objects the same way, accelerating their mass towards the center of the Earth at 10 meters/second. Once in the air, lift and angular momentum act on the Frisbee giving it a ballet-type performance. Lift is generated by the Frisbee's shaped surfaces as it passes through the air. Maintaining a positive angle of attack, the air moving over the top of the Frisbee flows faster than the air moving underneath it.
Under the Bernoulli Principle, there is then a lower air pressure on top of the Frisbee than beneath it. The difference in pressure causes the Frisbee to rise or lift. This is the same principle that allows planes to take off, fly and land. Another significant factor in the Frisbee's lift is Newton's Third Law which states that for every action there is an equal and opposite reaction. The Frisbee forces air down (action) and the air forces the Frisbee upward (reaction). The air is deflected downward by the Frisbee's tilt, or angle of attack.
Spinning the Frisbee when it is thrown, or giving it angular momentum (gyroscopic inertia), provides it with stability. Angular momentum is a property of any spinning mass. Throwing a Frisbee without any spin allows it to tumble to the ground. The momentum of the spin also gives it orientational stability, allowing the Frisbee to receive a steady lift from the air as it passes through it. The faster the Frisbee spins, the greater its stability.
For more information visit:-
http://en.wikipedia.org/wiki/Walter_Frederick_Morrison
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