Thread: Physics Quiz 4
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Unread 18-12-2011, 16:07
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Ether Ether is offline
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Re: Physics Quiz 4


Quote:
Originally Posted by Ether View Post

However, these 2 assumptions:
1: linear change in mu for angles between 0 and pi/2, and

2: mu is not increased by force components not in direction being considered
are I think open questions.

... I have looked but never seen any test data to show what happens when force is applied at a variety of angles between 0 and pi/2.

See attachments.

Plotting the "linear" model of μ vs θ in polar coordinates suggests it may not be a good model.

Perhaps an elliptical interpolation between μx and μy would be a better model. See attachments.

I haven't done the math yet, but I think the elliptical model will solve the "2 Newton paradox" discussed earlier in this thread.


Attached Thumbnails
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Name:	''linear'' interp.gif
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Name:	''linear'' & elliptical.gif
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Name:	mu elliptical eqn.gif
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Last edited by Ether : 19-12-2011 at 11:22. Reason: added additional graphics