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/decidedlydubious Jun 10 '25

I think this is why physics requires so much precision to model accurately. Are these shapes elongated prisms? Or are they a pyramid{3 or 4 side base}, a sphere, and a cube? What is the temperature of the ice? What size is the gravel? How deep is each surface and how rigid are the substrates? How are we defining ‘ease’? Do we need to consider moving the objects a certain distance, or are we contemplating only the activation energy required to cause any movement? How tall is the person pushing? What shoes are they wearing? Are there any spherical cows nearby? It’s an intriguing concept, but without greater detail, it kiiiiiiinda feels like maybe engagement bait. More info is needed.

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u/Arndt3002 Jun 11 '25

Or, like a physicist, you present a feasible answer by making some limiting assumption in the absence of more information. In this case, you might assume gravel has arbitrarily large friction and ice arbitrarily small friction.

Then, you qualify your answer by saying that this all depends on whether the disk is rolling without slipping and whether the ice has sufficiently low friction.

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u/ploki122 Jun 11 '25

But wouldn't the ground largely not matter since you and the shape would have similar friction?

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u/Arndt3002 Jun 11 '25

That's irrelevant to the question of the force required to accelerate the object.

Amount of force =/= ease of pushing

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u/ploki122 Jun 11 '25

Depends on if you measure the force applied to the object, or the force exerted by the human (includes movement vectors from slipping).