I Why Do Fractions Like 2/3 and 3/2 Frequently Appear in Physics Problems?

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AI Thread Summary
Fractions like 2/3, 3/2, 2/5, and 5/2 frequently appear in physics problems due to their association with simple exact solutions designed by educators. These values often emerge in scenarios involving contact points, such as masses losing contact with spheres or the minimum height for loops in motion. The discussion suggests that this phenomenon parallels the use of specific triangles in trigonometry and the prevalence of rational coefficients in moment of inertia calculations. Additionally, there is a mention of the frequent appearance of 1/2 and factors of powers of 2π in formulas, attributed to their mathematical origins. Overall, the thread highlights a tendency towards these fractions in physics problem-solving, raising questions about their fundamental significance.
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So I noticed something about problems. I see the number 2/3 or 3/2 a lot. For example, the height masses lose contact with sphere. Ladder losing contact with wall etc. Or 3/2 for the height above a rolling cue ball to strike for it to stop etc. And I notice the number 2/5 and 5/2 a lot as well. For example, the minimum height to make around the loop de loop.

Is there something more fundamental going on here?
 
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I think this is a result of teachers designing problems with simple exact solutions. This is not unlike the use of 30-60-90 or 45-45-90 triangles in trig or Pythagorean triplets i.e. 3-4-5 right triangles when teaching the Pythagorean theorem.
 
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FallenApple said:
So I noticed something about problems. I see the number 2/3 or 3/2 a lot. For example, the height masses lose contact with sphere. Ladder losing contact with wall etc. Or 3/2 for the height above a rolling cue ball to strike for it to stop etc. And I notice the number 2/5 and 5/2 a lot as well. For example, the minimum height to make around the loop de loop.

Is there something more fundamental going on here?

I have noticed lots of 1/2 popping up recently. There must be a nest somewhere.
 
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The worst are factors of powers of ##2 \pi##. They tend to be missing or appear to often in formulae. In this case you can trace it to Fourier as the culprit. LOL.
 
vanhees71 said:
The worst are factors of powers of 2π.
Use τ.
 
vanhees71 said:
##\tau##?
 
FallenApple said:
Is there something more fundamental going on here?
Yes, you've fallen into the trap of numerology :smile:
 
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phinds said:
Yes, you've fallen into the trap of numerology :smile:
Have you fallen into the trap of necroposting?

Too easy.

Thread locked.
 
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