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Unread 13-01-2013, 21:03
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Re: 2 wheels vs 1 wheel in a linear shooter

Quote:
Originally Posted by Ether View Post
With 2 wheels, the maximum frisbee speed is still half the wheel tangential velocity.
I also followed your math here:

Quote:
It translates into approx 21 mph, assuming no slipping.

3600 rpm / 60 min/sec = 60 rev/sec

60 rev/sec * pi*4/12 ft/rev = 62.8 ft/sec

62.8 ft/sec / 2 = 31.4 ft/sec

31.4 ft/sec * 3600 sec/hour / 5280 ft/mile = 21.4 mph
I understand that the rotation of the frisbee as it contacts the wheel causes less than its full velocity to be transferred in an ideal situation, however why is it that the maximum exit velocity of the frisbee will theoretically be one half that of the tangential velocity of the wheel?
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Unread 13-01-2013, 21:23
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Re: 2 wheels vs 1 wheel in a linear shooter

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Originally Posted by boarder3512 View Post
why is it that the maximum exit velocity of the frisbee will theoretically be one half that of the tangential velocity of the wheel?
Think of a car traveling down the highway at 60 mph.

The geometrical center of each tire is traveling at 60 mph.

At any instant in time, the bottom of each tire is traveling at 0 mph, and the top of each tire is traveling at 120 mph.

It's the same with the frisbee.



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Unread 13-01-2013, 21:58
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Re: 2 wheels vs 1 wheel in a linear shooter

Quote:
Originally Posted by Ether View Post
Think of a car traveling down the highway at 60 mph.

The geometrical center of each tire is traveling at 60 mph.

At any instant in time, the bottom of each tire is traveling at 0 mph, and the top of each tire is traveling at 120 mph.

It's the same with the frisbee.



Makes sense - thanks for the explanation.
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