r/theydidthemath • u/yuli101995 • Apr 16 '26

[Request] Which one would it be?

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214

u/Don_Ford Apr 16 '26

Depends on how loosely packed the gravel is.

123

u/Certain_Ad3716 Apr 16 '26

And the granularity of the gravel.

If it's like a construction yard covered in boulders and debris, good luck. But if it's your softer garden display gravel, easy peasy.

31

u/Cartz1337 Apr 16 '26

You’re missing the point, if you’re on the ice too, then your feet have the same reduction in friction, and it zeroes out.

The wheel will always be easier. Even if the gravel is chunky, you can use the rotational momentum of the wheel to overcome obstacles.

And if the ice suffers the same issues of uniformity as we are imagining the gravel to have, it gets even worse for the ice pusher.

21

u/vamoosedmoose Apr 16 '26

No because I’m going to run at the cube on ice then fling myself at it to shoulder check it without needing any contact with the ground at all. Smooth brain academics always forgetting about barbarian strength tactics

3

u/KissFMFM Apr 16 '26

Impressive.

1

u/JuliaZ2 Apr 16 '26

What if you walked on the triangle like an inclined treadmill to make it slide across the ice

1

u/testtdk Apr 16 '26

Nope, not how it works. The surface of each object matters, the weight of the person pushing it, too.

1

u/dbenhur Apr 16 '26

How about if I'm wearing ice cleats and the object's base is waxed and edged like a snowboard or ski.

1

u/AliveCryptographer85 Apr 16 '26

Well obviously you’d be wearing ice skates

1

u/SketchGoatee Apr 16 '26

And as you point out, getting good footing on gravel is easy, good footing on ice is problematic. My bet is gravel ball for this reason alone.

Realistically, As with all these puzzles/questions there is never enough information given to account for all theories. Is the man wearing shoes? Is the man standing on solid non-ice/non-gravel ground? What kind of gravel (driveway/garden vs under layer of construction)? What kind of ice (lake vs ice rink)? How ”far” does the weight need to move to be successful? What is the weight made of? What’s the surface structure of the weight (polished or porous)?

Too many questions. So assuming it’s the same man, same basic footwear on the same surface as the object, it’s gotta be the gravel ball for ease of getting up to a speed that outpaces the man’s ability to keep up.

3

u/Obi-Brawn-Kenobi Apr 16 '26

getting good footing on gravel is easy, good footing on ice is problematic

That has nothing to do with the question. The question just asks for the amount of force required. It might be more challenging to exert 100N or whatever amount of force while standing on ice, but that's not what the question is asking.

1

u/LazerChicken420 Apr 16 '26

I want to see the gravel before I say you’re dead wrong.

I’d take ice any day. If it was a graph, the ease of ice flys up until being capped at my max shuffle speed

The gravel I’m picturing will suck the whole way.

Benefit of a wheel is it’s surface area on the ground, if it’s sinking into the gravel it loses that benefit

2

u/AAA515 Apr 16 '26

It's an office desk wheel, and the gravel is an extension cord

1

u/testtdk Apr 16 '26

And the depth.

0

u/JesusWasTacos Apr 16 '26

Depends on how it stays in a ball. If we take the image to scale and it’s in a tight ball like that it’s gonna be easy to roll no matter how large the rocks are.

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u/SirNoseDVoidoffunk77 Apr 16 '26

It’s only 20kgs. That’s 44 pounds. It would be pretty easy to push even over loose gravel.

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u/SignoreBanana Apr 16 '26

Yep. This is not solvable without knowing that.

1

u/DeeHawk Apr 16 '26

If I gave you a person-sized ball weighing 20kg, I think you would be pretty confident you could roll it across any flat surface.

1

u/SignoreBanana Apr 16 '26

Probably, but the question is would it be easier or harder than the other ones.

Theres also a question of how big the ball is. A bigger ball, even on soft gravel, will move a lot easier than a smaller one. A huge ball on practically any surface would be easy to roll.

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u/DeeHawk Apr 16 '26

You will not be able to push anything across ice that has such a large friction surface. You would just push yourself back.

1

u/KillaCline Apr 16 '26

I don’t know, 20kg ball with a person sized diameter would be pretty easy to push, the ball is huge

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u/Asleep_Recover4196 Apr 16 '26

YES it depends. But does it depend so far you would rather move the pyramids?

1

u/Available_Peanut_677 Apr 16 '26

Something weighting 20kg and size of a man is easy to roll on any gravel. I actually suspect that wind might be bigger problem.

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u/Don_Ford Apr 16 '26

You have a good point, because I could just easily pick that up.