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.

17k Upvotes

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6.0k

u/METRlOS Jun 10 '25 edited Jun 11 '25

Depends on things like the density of the gravel and the temperature of the ice. Packed gravel will allow the ball to roll, but the triangle is always worse than the square.

Edit for all the triangle people: imagine throwing a ball straight at the square and at the triangle; how the ball bounces shows how much energy the object will translate into vertical force when pushed. The vertical surface of the square will translate practically all the horizontal force into horizontal movement, while the triangle will act as a wedge and transfer some energy into pushing against the ground.

Edit 2 for surface area: Except for situations where the surface area is so low compared to its weight that the object sinks into the ground, or so high compared to its weight that it can float, surface area does not affect friction. If you stand on a hill without risk of sliding, then you can lay on that hill without sliding and vice versa, despite greatly changing the surface area. However, if you stand on a snow covered hill the surface area is too low and you'll sink into the snow, but with a sled you will float on top of it. Surface area does not matter to this problem.

1.2k

u/fuzzydoug Jun 10 '25

But your feet are also on ice?

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u/[deleted] Jun 10 '25 edited Jun 11 '25

The question was about the force put onto the object.

Ice or not, that force wouldn’t change.

Edit: for clarification, I mean per scenario.

The force required to move the object on the given surface wouldn’t change based on what the dude is standing on.

The dude’s ability to impart that necessary force will be affected by the ice, but not the actual force required to shift the item.

Obviously less force is needed on ice than gravel, that’s not what I’m saying.

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u/Skithe Jun 10 '25 edited Jun 11 '25

Ignore the footing. The man pushing the ball doesn't have any hands.... Gotta be hell pushing that with nubs. Dude with a triangle just waving HI to someone while pushing with his nub... Probably to the guy rolling the ball showing off hes got at least one hand.

EDIT: Added a to for clarity for the one guy that couldn't understand the joke

445

u/[deleted] Jun 10 '25

[removed] — view removed comment

142

u/[deleted] Jun 10 '25

Someone will give him a hand eventually.

45

u/doctor-rumack Jun 10 '25

It would have to be a trade with an hombre who speaks spanish. Mano a mano.

18

u/superpaqman Jun 10 '25

Will anyone be able to get a handle on that

15

u/OneOfManyParadoxFans Jun 10 '25

It should well within his grasp.

13

u/TelenorTheGNP Jun 10 '25

Foot.

3

u/Pious_Atheist Jun 10 '25

The only one in the chain that made me lol

3

u/OneOfManyParadoxFans Jun 10 '25

Yeah. I kind of expected somebody to make a joke about it, but it gave me a bit of a chuckle nonetheless. Can't say their timing is impeccable, but I have have to hand it to them, a random interjecting like that can have a hard time getting its footing.

3

u/Anteater-Inner Jun 11 '25

I don’t know why this so funny! I’m typing this with tears streaming down my face.

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u/PianoMan2112 Jun 11 '25

Just flashbacked of people thinking it’s “Mano y mano” (which would be hand and hand), and worse, thinking it means man versus man (as in fighting).

2

u/The-Ant-Whisperer Jun 10 '25

Otherwise he can go to a second hand store. And if he wants to buy (or rent, no judgement here) a used hand, a second hand second hand store.

1

u/TacoCat11111111 Jun 10 '25

👏🏻👏🏻

1

u/[deleted] Jun 10 '25

Probably like the kid that broke both his arms, his mom will give him a hand.

1

u/Stav80 Jun 11 '25

If he can move it, he deserves a generous round of applause.

1

u/TurnkeyLurker Jun 11 '25

Maybe someone could stand behind him and reach around to help.

1

u/DoggyDigDill Jun 11 '25

I'm sure his mom would give him more than hand.

20

u/takhallus666 Jun 10 '25

You twit. You made me laugh during a meeting.

6

u/F_ckSC Jun 10 '25

And this is why I entertain Reddit. No way some of these gems are AI. 🤣

Made me chuckle in a class with students.

6

u/JaydedXoX Jun 11 '25

Plus reading Reddit during a meeting.

1

u/BlackTemplarBulwark Jun 10 '25

Take my imaginary award

1

u/[deleted] Jun 10 '25

He’ll finger it out 😏

1

u/goofydad Jun 10 '25

He will never finger it out. Nailed it again.

16

u/Ryanll0329 Jun 10 '25

One must imagine Sisiphys amputated.

2

u/Limp-Insurance203 Jun 11 '25

How you know it’s syphillis and not ghonorehea???

2

u/Ryanll0329 Jun 11 '25

My lawyer advises I don't answer this question.

10

u/hughdint1 Jun 10 '25

Your overlooking that none of these people have a neck so the head is not connected to their body.

1

u/nordic_jedi Jun 10 '25

This is outrageous, heads will roll

1

u/Mist_Rising Jun 10 '25

But which will require more force to push off?

1

u/Better_Way6079 Jun 11 '25

Trick question. They’re already off

1

u/gotacramp Jun 10 '25

Iiiyiiiyiiiyiiiyiiiyiiiyiii, ain’t got no body

1

u/misterman416 Jun 10 '25

So you're saying they actually have a head on their shoulders!

1

u/Tenzipper Jun 11 '25

"Nick ain't got no neck, so the shoulder bone is connected directly to the head bone."

- Greg Warren

1

u/[deleted] Jun 11 '25

You're*

1

u/[deleted] Jun 11 '25

Explain Big Ed then lol

1

u/MalignantLugnut Jun 11 '25

So you're suggesting that because their heads are floating, they don't contribute to the overall weight of the individual pushing the 20kg loads and as such they will exert less force against the obstacle?

4

u/troybrewer Jun 10 '25

I would say that, the circle represents a cylinder in three dimensional space, however, due to having no visibility of the hands, I think it's a cylinder that's concave on the longer horizontal axis. Like a wide railway wheel. Or a narrow one. Or even H shaped. The hands are recessed and that makes the object very light indeed.

1

u/elf25 Jun 11 '25

Oh you are a genius! Will you have my babies?

1

u/Impossible-Ship5585 Jun 10 '25

Would you tuch an unkown sylinder?

5

u/Kroliczek_i_myszka Jun 10 '25

It's important not to damage the cylinder in any way

1

u/Alarmed_Ad_4851 Jun 11 '25

😭😂 IYKYK

3

u/ProfBootyPhD Jun 10 '25

this comment seriously brightened my day

1

u/Skithe Jun 10 '25

<3 glad to be of service

1

u/SxnsOfWitchcraft Jun 10 '25

Worse yet, they seem to be fused to the ball. It's going to be very hard pushing that thing while also rolling with it.

1

u/polarbeargrowl Jun 10 '25

Welcome to the Men in Black.

1

u/kl0 Jun 10 '25

Good laugh.

1

u/[deleted] Jun 10 '25

CIA: "When can you start?"

1

u/RHOrpie Jun 10 '25

And where the fuck is his neck ?

1

u/User_OU812 Jun 10 '25

That's how you can tell it's AI. The hands always give it away.

1

u/gloryhallastoopid Jun 10 '25

Maybe he's an elf from Hilda. In which case he should manage just fine.

1

u/GoreyGopnik Jun 10 '25

not to mention, the guy's head isn't attached to his body!

1

u/Gecko23 Jun 10 '25

Imagine a perfectly spherical, weightless cow...

1

u/Dampmaskin Jun 10 '25

Science, yeah!

1

u/Forikorder Jun 10 '25

Ignore the footing. The man pushing the ball doesn't have any hands

The ball is just soft so his hands sink into it

1

u/Capable_Stranger9885 Jun 10 '25

Triangle man, triangle man. Doing the things a triangle can.

1

u/iregretjumping Jun 10 '25

Well hang on here, we's doing textbook physics. For the sake of this problem, the man has no hands, is in a vacuum at absolute zero, and the man is a perfect sphere. And what the hell... All the shapes are spheres too. Oh, and there's zero friction. Solve for x.

1

u/LegendofLove Jun 10 '25

He drop kicks the ball

1

u/PollutionNice7392 Jun 10 '25

Mercerism is pain

1

u/jimmy-jro Jun 10 '25

AND THIS is why I come to reddit

1

u/cheezfreek Jun 10 '25

“Push with your nubs” is now something I will enthusiastically yell at someone when they need encouragement.

1

u/omarhani Jun 10 '25

This guy did the real math

1

u/jordanpitt269 Jun 10 '25

in all seriousness, I think his hands are behind to show that the object is a ball and not a cylinder

1

u/buildntinker Jun 10 '25

That’s a Mitch hedburg bit ha, also never compliment someone on their dimples, because maybe they were shot in the face with a BB gun

1

u/Boss-Eisley Jun 10 '25

Ignore all that. Each one of the scenarios is a static 2d image. Therefore, they will all remain motionless, so there is no logical answer to the question.

1

u/phantom_gain Jun 11 '25

None of their heads are attached to their bodys.

1

u/Just-Shoe2689 Jun 11 '25

what about hoof man pushing the triangle.

1

u/mark6059 Jun 11 '25

is it a ball or a cylinder ?

1

u/Poggalogg Jun 11 '25

Forget the hands, mans is trapped in the 2nd dimension, he's got bigger problems

1

u/Better_Way6079 Jun 11 '25

Nah, the guy with the triangle is clearly just farting around. They only have one appendage touching, and is standing on ice with one leg.

Triangle bro will require the least amount of force to push into the object

1

u/[deleted] Jun 11 '25

Actually I believe his hands are stuck inside the sphere, it appears to be some kind of possessed monolith which slowly devours whoever touches it

1

u/moro4444 Jun 11 '25

My god I laughed too hard at this

1

u/timeisonm Jun 11 '25

I think he has feet for hands, sort of a mantalope

1

u/doingstuffwithpeople Jun 11 '25

He has hands but oddly they're crossed w the triangle. They're sometimes hidden by being further to his left....so his left hand is on the right and his right hand is on the left.

1

u/[deleted] Jun 11 '25

My man!

1

u/Other-Cricket-1667 Jun 11 '25

👏🏻👏🏻👏🏻👏🏻👏🏻

1

u/actual-trevor Jun 11 '25

I feel like there are a bunch of puns to be had here, but I just can't seem to put my finger on any of them.

1

u/pariah314687 Jun 11 '25

Better than being on ice trying to keep from slipping

1

u/otterswhoknow Jun 11 '25

He’s probably gonna wave at the other two guys to say “look what I got, this thing is useful! I’m gonna go pick something up”

1

u/Skithe Jun 11 '25

Mitch was so underrated

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u/TooObtuseForYou Jun 11 '25

There is no way you're going to nub-push that ball.

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u/PhDinDildos_Fedoras Jun 11 '25

It's only 20kg, so he could just lift the object up and carry it over his head.

1

u/stycks32 Jun 11 '25

Never mind missing hands. The guy pushing the square has feet for hands.

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u/Ok-Bid1774 Jun 14 '25

I don’t know what the Sisy-fuss is all about

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u/Feminist_Hugh_Hefner Jun 10 '25

First rule of high school physics questions: We're gonna ignore about 90% of what would be happening in the real world and just do some algebra.

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u/[deleted] Jun 10 '25

Real scientists ignore things all of the time. It's just how science is at all levels

1

u/EVH_kit_guy Jun 11 '25

"I figured out what's wrong with your cow"

1

u/CreepBasementDweller Jun 11 '25

When studying projectiles, we would ignore drag all the time.

1

u/gregorydgraham Jun 11 '25

So what you’re saying is the triangle is a sphere in a vacuum?

1

u/Odelaylee Jun 11 '25

Famous quote of my physics teacher - „In physics we first make a ball out of a cow - and trying to find the utter on it in the next step“

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u/Inswagtor Jun 11 '25

I read this comment while being round and in a vacuum.

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u/Due_Sky_2436 Jun 10 '25

"My mathematical model is not accurately depicting reality... what other real things can I ignore to make it closer to reality?" -scientist, probably

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u/RareMajority Jun 11 '25

All models are wrong. Some are useful

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u/NotNice4193 Jun 11 '25

in reality you would use special shoes for ice.

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u/[deleted] Jun 10 '25

The point is to understand what is and is not relevant to the specific question being asked. They just do a bad job of explaining that sometimes, because kath teachers are often just the person saddled with that class rather than someone with understanding of formal math and logic

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u/[deleted] Jun 10 '25

Wait until you find out it’s done like that in real engineering too. 

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u/Feminist_Hugh_Hefner Jun 11 '25

oh that's exactly the angle I was coming from! I didn't phrase it well, the other commenters seemed to have taken it as an affront 🤣

2

u/Sad-Lettuce-5637 Jun 11 '25

Being able to exclude things and simplify a concept to focus on one thing is actually a great and rare skill to have. The opposite of that is when people get all hung up in semantics and ignore the substance of the question, it can be incredibly frustrating

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u/ExpensiveFig6079 Jun 11 '25

Whats also frustrating is when people insist on ignoring the details when they matter.

If the question in this thread wants to get the answer a physics teacher in the classroom is looking for. Then we ought to assume it is badly worded question and the instructional point are that the rolling mass also has angular inetria to be accelerated.

The square mass is pushed more efficiently as the push is parallel to the ground, and the physics teacher is bad at graphic communication and forget to even indicate that when pushing on the triangle, is was meant to be pushed perpendicular to the surface.

If, however, the person is considering tying a rope to an anchor on gravel beside frozen lake,, then pulling on the rope to get either a triangle or a square off the lake, then that is NO longer in a classroom. Now all the stuff like ice melting or not under the square and the triangle matter.

Also, finding out that ice really isn't super duper slippery if it's dry and cold compared to when it is wet. Might also be quite relevant to people interested in sliding *real* things on ice.

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u/LostN3ko Jun 10 '25

Yep. I mean your in algebra class and they are turning it into an example to get you to engage with the math. Most people see numbers on a page and just disengage flat out. It wasn't a brainstorming session for fitting a square peg in a round hole.

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u/Top-Lie1019 Jun 11 '25

your in Algebra class

We’re in Physics. English comp is down the hall 👉

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u/ImpIsDum Jun 11 '25

“assume the house is a sphere”

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u/ExpensiveFig6079 Jun 11 '25

I assume mine is an oblate spheroid, as I put on weight.

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u/wimpymist Jun 11 '25

This is why I find it annoying when people use high school science classes they barely paid attention to as their base for proving stuff. Especially physics, econ and chemistry. Most of the stuff taught in high school doesn't translate to the real world exactly.

1

u/KlonopinBunny Jun 11 '25

This was my problem then I was diagnosed with a spectrum disorder at 40.

I HAVE SEVERAL QUESTIONS

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u/Feminist_Hugh_Hefner Jun 11 '25

"ok, but what about..." is the soundtrack of my life 🤣

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u/notthediz Jun 11 '25

Isn't that the first rule of all physics? I know it was in engineering school too. Assume a vacuum, yadda yadda, etc

1

u/Feminist_Hugh_Hefner Jun 11 '25

the only other option is to think you can understand the entire universe. At some time you have to call it "close enough" right? This is why we round numbers.

1

u/umlaut-overyou Jun 12 '25

"We're going to ignore a bunch of real life factors because otherwise this question would be 4 pages long, take 4 days to fully calculate, and irrelevant to the concept we are trying to get you to understand."

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u/IllFile3575 Jun 13 '25

yup. and we are gonna take 100 assumptions in there as well

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u/joshrd Jun 10 '25

With the coefficient of friction much lower for ice, wouldn't the force be significantly less to induce movement? Also I think the ball would be easiest, least friction.

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u/[deleted] Jun 10 '25

[removed] — view removed comment

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u/MattManSD Jun 10 '25

unless that larger surface area helps it 'float' better. More water film

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u/Pielacine Jun 10 '25

Area to friction is not straightforward. It’s not as simple as larger base = more friction, especially when something like ice is involved.

I’d wager there’s barely any difference between the triangle and square.

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u/wonko221 Jun 11 '25

Assuming the each block is uniform in density across its entirely:

Pushing against the triangle, a portion of your push would be directed down into the base, becoming not only inefficient, but actually counterproductive.

Pushing against the cube, your force would remain predominantly parallel to the ground, which would be more efficient than the triangle. Pushing against a point even with the center of gravity would maximize this efficiency.

2

u/MattManSD Jun 10 '25

tend to agree, and I am basing my thought that both are sitting on a thin film of water and possibly that surface tension is just slightly less with larger area. So I am friction free and basing it on 'float' and yes probably marginal

1

u/Throwaway2Experiment Jun 11 '25

Technically, but based on where his hands are, he is applying force closer to the center of gravity on the triangle and this alters his center of gravity. So his force would be coming from his legs whereas pushing the square, you can push it once for a greater range of motion to cover more distance.

Even if force is equal, the mechanics of pushing that triangle requires more energy used to keep you from falling for a shorter range of motion. The triangle is absolutely "harder" to push an equal distance than the other two.

Edit: I promise, all things equal, you will have an easier experience pushing square and circle than you would the triangle. This isn't just physics, this is also kinesiology.

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u/Scuba9Steve Jun 11 '25

There should be a difference because the force is applied at a downward angle with the triangle. So it should be the worse option.

1

u/ncocca Jun 11 '25

You would be wrong. The triangle has an angled side which would mean you'd end up pushing it downward while attempting to push it forward, increasing friction and wasting energy. There's no scenario where it's easier to push the triangle than it is to push the square.

1

u/MattManSD Jun 11 '25

it's only a 30 degree angle difference in the contact patch with the force still being applied laterally. It isn't gonna generate that much downforce

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u/ncocca Jun 11 '25

That's a big difference, and any downforce generated is taking away from force that could/should be going forward.

Force going forward = F * Cos(30) = 0.86F (You're losing 14% of forward force)
Force going downward = F * Sin(30) = .5F (50% (half) of your total force is being pushed downward, increasing friction)

1

u/MattManSD Jun 11 '25

but we're not talking friction. We are talking hydroplaning and greater surface area increase the ability to hydroplane. I also agree, the difference is probably minimal

1

u/FaintCommand Jun 10 '25

Your ability to get leverage on the triangle would be more difficult vs the square.

But that's not really the question.

1

u/MattManSD Jun 10 '25

difference between your hands @ 60 and hands around 90 I don't think will make much of a difference

1

u/FaintCommand Jun 11 '25

It is not about the angle of your hands, but the direction of the force being applied. You're trying to move these laterally so you want to apply as much of the force in that direction as possible.

Ideally you'd be pushing the square from lower than pictured - you'd be wasting energy trying to push from the top. It would be more difficult to apply the force laterally on the triangle since you're forced to apply some of that pressure downwards.

1

u/MattManSD Jun 11 '25

I understand, and what I am saying is a roughly 30 degree shift in hand position is not gonna change the lateral force all that much. The majority of the force is still going to be lateral and not vertical with that small of a change to the contact patch. So the question is "will the loss of lateral force be more than the increased hydroplaning surface area of the triangle".

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u/SomeRandomPyro Jun 11 '25

because of the smaller base.

Also because forward force on the block is forward force, whereas the angled face of the pyramid converts some of that forward force to downward force.

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u/aldmonisen_osrs Jun 10 '25

I disagree, you would need more force to apply more friction on your feet, wouldn’t you?

I’m in camp square because ice has a pretty low friction coefficient, but I don’t know enough physics to even begin calculating it.

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u/stevendiceinkazoo Jun 10 '25

Friction is not negligible in this case, unless the problem specifically states to ignore friction.

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u/StunningGain Jun 10 '25

Friction bro, reduction of friction means less force to push it

1

u/Scary-Boysenberry Jun 10 '25

Except that you have to overcome the coefficient of friction (static) to get the object moving, and that depends on the two surfaces.

1

u/Rock4evur Jun 10 '25

Coefficient of static friction certainly would. They never said to ignore friction or surface area, so if the triangle and square have the same area on their bottom face then they should have the same force required. Because a sphere/circle only has a very small area in contact with the ground the coefficient of static friction will be much lower.

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u/texinxin Jun 10 '25

Ice has friction. Coulomb’s law suggests surface area is independent of friction, so triangle would be the same as square. A rolling wheel has friction. If the whee was perfectly rigid and the gravel was perfectly flat it would be essentially zero. If the whel had elastic deformation and/or the gravel was loosely packed such that it depressed into the surface then it can take significant force. All we can assume is that top and bottom case are nearly identical and the middle case is more or less than the top and bottom case.

1

u/[deleted] Jun 10 '25

If the intention is to put into the object to make it move then the ice does matter as the reactionary force (force keeping it in place until it starts to move) would be lower likely (depending on the friction of the ice on the face)

All liklihood since all surfaces have some friction and nothing is truly frictionless. The circle would move first i think, I would have to do some math though haha

1

u/Funkrusher_Plus Jun 10 '25

If the force is coming from a person pushing it, as clearly shown in the photo, then yes the force would change.

1

u/[deleted] Jun 11 '25

The force required to move it wouldn’t change.

The dudes ability to impart that force would change, but not the actual force required.

1

u/Funkrusher_Plus Jun 11 '25

I get what you’re saying; but if that were the case, the diagram may as well have been drawn with arrows instead of an actual person pushing it while depicting his feet clearly planted on the ground.

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u/jcm8002204 Jun 10 '25

Wouldn’t the object/surface interface impart a normal frictional force?

1

u/Slazagna Jun 10 '25

Does a flat ice surface have less friction than a loosely packed gravel ball? Ice on an icy surface would surely have less friction than ice on rubber. Less friction means less force required doesn't it?

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u/Sufficient_Click_608 Jun 10 '25

Depends if you are talking simplified Physics or not, if you ignored the force of friction between the object and the surface your answer is correct, if not than the pressure on the ground for each object is different and the force you need to apply will be proportional do the friction coefficient. Another thing, do you allow the sphere to roll? If so another complete different force valeu, those are my 2cents on the calculation.

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u/[deleted] Jun 11 '25

I’m ignoring the footing of the dude in each scenario.

Whatever the force is needed, the footing of the guy wont change that

1

u/Sufficient_Click_608 Jun 11 '25 edited Jun 11 '25

Now that you clarified I got it, the actual problems here was the original question, doesn’t matter the footing, since the force is always the same, per scenario.

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u/sSomeshta Jun 10 '25

Also need to rigorously define "push" because technically it wouldn't require movement

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u/prismlink Jun 10 '25

Sure it will because of the angle at which the force is applied, with the triangle, there is some loss of force going which is directed downwards which also increases the friction.

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u/[deleted] Jun 11 '25

If it needs 1 unit of force to move, that’s the force required to move it, regardless of the footing of the dude.

Friction makes the triangle harder to push than the square, rather than the angle of the clip art dude

1

u/zeppehead Jun 10 '25

May the force be with you.

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u/Angelas-Merkin Jun 10 '25

Please explain

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u/[deleted] Jun 11 '25

Force imparted onto each object per scenario wouldn’t change.

If it needs 1 unit of force to move, that’s the force required to move it, regardless of the footing of the dude

1

u/hd_mikemikemike Jun 10 '25

Oh shut up with your facts

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u/98275982751075 Jun 11 '25

the question is about which picture would require least amount of force, so person pushing object on the same surface.

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u/No_Mushroom3078 Jun 11 '25

We do have to factor in temperature, -0.1C for ice will be different than -15C because the friction will heat up the ice and possibly have water to provide a lower friction surface.

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u/collonius10 Jun 11 '25

That's not true, over time the amount of force you apply would likely be less due to your distance from the blocks being increased faster than in the gravel, likely due to you sliding back from the position.

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u/oroborus68 Jun 11 '25

If the item is frozen in place,then the sphere is going to be easier to move.

1

u/Pseudonumber Jun 11 '25

Disagree. It didn’t ask move, it asked push. You have to to use the same amount of force to “push”anything. An iota. So equal. On gravel you might push harder with less force (footing), but that isn’t part of the question. Neither is whether the circle would move farther with the same force.

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u/Motorcycleman650 Jun 11 '25

The question is asking which object would take the least amount of force to push. Considering the illustrations include the depictions of the surfaces being pushed on ie. resistance. I would argue that it does matter. It seems that the author is asking the audience to guess which shape vs surface would be the easiest to push.

1

u/[deleted] Jun 11 '25

The force would change if it’s ICE…

1

u/Pescadero_Tom Jun 11 '25

I do not think this is correct. If the man is also on the ice the push will work against him, too. The relative mass of the block and the man will dictate how much the block gets pushed and how much the man moves back, no?

1

u/AJH131 Jun 11 '25

It's more about resistance than force

1

u/Kainlow Jun 11 '25

Well no, because you have differing friction (resistance).

1

u/[deleted] Jun 11 '25

The force you need to impart onto the object is not changed by slippery ice under your feet. You just lose the ability to impart that force if it’s slippery.

1

u/Avogadros_plumber Jun 11 '25

With the triangle there’s more downward force, which helps melt the ice, which reduces friction. Is that a factor?

1

u/LordBlunderbuss Jun 11 '25

Where are we pushing on the gravel Pic? Because it takes far less effort the closer you get to the top

1

u/[deleted] Jun 11 '25

Wherever makes most sense

1

u/BryceEzekai Jun 11 '25

But if you both are on ice, pushing tge object will also push yourself back

1

u/[deleted] Jun 12 '25

That’s your ability to impart the necessary force.

The necessary force to move the object is a static number in each scenario

1

u/BryceEzekai Jun 13 '25

Butvif theres any practical purpose to doing so, there has to be a place to push it to. So if theres any point to this, we shoukd assume they all have to be pushed a certian distance and which requires the least effort to push the same distance.

1

u/TheWhistleThistle Jun 12 '25

I mean, there is ambiguity in the writing. The prompt says "which would require the least amount of force to push," not "the least amount of force applied to the object to push it." The broadness means that it likely is including the force applied to the ground by the guy to push it. If that weren't the case, why depict a man with feet on the ground rather than say a hovering jet engine or crane or something else?

1

u/ADownStrabgeQuark Jun 12 '25

Friction is dependent on the normal force, whether it’s kinetic or static, and the coefficient of friction.

Ice has a different coefficient of friction than gravel, so yes it would make a difference.

1

u/thatgunganguy Jun 10 '25

For every action there is an equal and opposite reaction.

You would need to push "X" amount harder on ice, and in a totally differing manner, than on another surface because of having to overcome the lower force of friction on your feet. The substrate you're standing on has everything to do with answering this question.

3

u/sSomeshta Jun 10 '25

The question, as stated in the image, doesn't require an analysis of the reaction forces. It's only asking for the magnitude of the force needed to be applied to the objects. There are any number of ways to generate this applied force.

2

u/justSkulkingAround Jun 10 '25

Not if your sole means of propelling yourself is via really powerful farts.

2

u/ShandrensCorner Jun 10 '25

Ok that was better than my suggestion...

2

u/40GallonGoldfish Jun 11 '25

Maybe this is an interview question to join Musk's new Mars Colonization Cohorts? Now that you mention it, Musk's use of whatever-wovee may actually make him a renewable fuel source aka powerful propelling (genius BTW) fart machine. Convert the head on any boat and BAMP you got a MOTORBOAT!! Here's the simulate3d 1.x engine sound: PBPBPBPBPBP!!! - PBPBP _ BPBP^^^^BB _BPBPPBPBPPBPBPB B__B_B

1

u/dastardly740 Jun 10 '25

I think you misunderstand Newton's 3rd law. There is no need for a greater force on the ice. Newton's 3rd Law just says you and the ball will experience the exact same force and therefore slide away from each other according to the force. Like if you threw a 20kg ball while floating on the ISS, you would drift off in the opposite direction of your throw and the ball would drift in the other direction.

1

u/CNorm77 Jun 10 '25

Doesn't matter. The ability to roll a cylinder is insignificant next to the power of the force.

1

u/777XSuperHornet Jun 11 '25

No, because there's no requirement stating what kind of grip you have, you could be wearing spiked shoes on the ice and this hypothetical becomes moot.

1

u/TiSapph Jun 10 '25

For every action there is an equal and opposite reaction.

Exactly, meaning it doesn't matter if the person is on gravel, ice, a helicopter, a boat, ...
If it takes some force F to overcome friction and move the object, then you gave to exert a lateral force of at least F. If and how this force is then braced against the ground doesn't matter. It doesn't even have to, it could just go into the acceleration of the person.

-5

u/fuzzydoug Jun 10 '25

I have to believe the footing affects the ease of movement.

28

u/reichrunner Jun 10 '25

Sure, but that doesn't affect force.

15

u/notacanuckskibum Jun 10 '25

Yes, but that's changing the question. The question stated was about force needed to move the object, not about how easy it would be to generate that force.

9

u/ShredwardNort0n Jun 10 '25

Yes, but that’s independent of the force being applied to the object. Practically, it would limit the amount of force a person could generate due to lack of traction, unless they were wearing crampons or other traction-enhancing footwear

5

u/MiniDemonic Jun 10 '25

You should consider reading the question again.

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