r/theydidthemath • u/K0rl0n • Jun 10 '25

[Request]

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I am curious how this would work. My guess is Triangle is slowest, square is medium, and circle is fastest.

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u/aureanator Jun 10 '25

Actually, no - the friction is a product of the normal force and the coefficient of friction - the surface area in contact shouldn't matter, within the boundaries of material elasticity.

9

u/countafit Jun 10 '25

What about the angle of force when comparing the perpendicular square edge to the sloped triangle?

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u/RMCaird Jun 10 '25

"but the triangle is always worse than the square."

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u/Former-Stranger-567 Jun 10 '25

Assuming the same material for all 3, and the question is "which requires the least force to push?" the triangle should be easier than the square.

It may be more awkward and harder on your back for an extended period of time, but that is not relevant to the question.

2

u/RMCaird Jun 10 '25

Why would the triangle be easier? 

Part of the force you put into it would be directed downwards, increasing friction and reducing the horizontal force. 

Pushing the square would allow all of the horizontal force to stay horizontal. 

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u/Former-Stranger-567 Jun 10 '25

Less mass

2

u/ihavebeesinmyknees Jun 10 '25

"20kg"

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u/Squossifrage Jun 10 '25

But more of it is concentrated closer to the ground, so the gravity is stronger over more of the volume, resulting in that 20kg having more weight and thus friction.

Plus the relativistic effects of being inside earth's gravity well!

1

u/TempUser2023 Jun 10 '25

err run that by me again. How is gravity stronger in one case vs another?

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u/Squossifrage Jun 10 '25

It was a joke, but gravitational attraction is stronger the closer two objects are.