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

[FallenApple]

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?

 

[jedishrfu]

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.

 

[robphy]

In the moment of inertia calculations of simple shapes, rational coefficients often occur.
https://en.wikipedia.org/wiki/List_of_moments_of_inertia

 

[A.T.]

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.

 

[vanhees71]

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.

 

[A.T.]

The worst are factors of powers of 2π.

Use τ.

 

[vanhees71]

$\tau$?

 

[Charles Kottler]

$\tau$?

 

[phinds]

Is there something more fundamental going on here?

Yes, you've fallen into the trap of numerology

 

[russ_watters]

Yes, you've fallen into the trap of numerology

Have you fallen into the trap of necroposting?

Too easy.

Thread locked.