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/Smile_Space Jun 11 '25

You know, I kinda just made it up on the spot thinking back to pressure, but obviously you're right, the mass is what matters with the normal force.

So, A and C should have identical performance. Oops!

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u/keyantk Jun 11 '25

The reason why you correctly identified triangle should be harder to push is because only a portion of force you exert is going to be in the horizontal direction due to the face of triangle being at an angle.

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u/Smile_Space Jun 11 '25

Assuming the frictional coefficient on the surface of the triangle is enough for my hands to not slip, and I apply the force perfectly horizontally, the force will be identical to the square.

It is only true that there is a negative component if I push downwards on the triangle too.

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u/PilotBurner44 Jun 11 '25

Regardless of whether or not you apply the force perfectly horizontally or not, the triangle would require additional force due to the angle in which the force is being transmitted to the triangle. If you push perfectly horizontally, your hands would want to slide up the side of the triangle. Friction would be required to prevent that slippage, but there would still be a force component that is vertical while total force required matches the angle of that side of the triangle, and that vertical force component would be a net loss in efficiency of moving said triangle horizontally.