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| fourfathom:
--- Quote from: electrodacus on February 14, 2023, 02:59:02 pm ---Explain also why will wheel's spin or not speed depending on the prediction you made. --- End quote --- Before we can do that you have to specify if the vehicle is massless, the gears/belts/axles/wheels are frictionless, and if the ice is truly frictionless. Without this information it's impossible to say. Or why don't you tell us? What point are you trying to make? Why don't you simplify, rather than complicate your experiment? |
| electrodacus:
--- Quote from: Nominal Animal on February 14, 2023, 08:31:30 am ---[Edited to add the illustration.] Can I ask you a simple question, electrodacus? I believe this would be illuminating for us both. Let's assume we have a vehicle much like your front-wheel-on-treadmill, rear-wheel-on-ground, but with a busted gearbox so that all wheels just turn independently and freely, without slipping at all. Say, it is being towed by something else. The radius of both wheels is \$1/(2\pi)\ \approx 0.159\$ length units (diameter \$1/\pi \approx 0.318\$ length units), so that their circumference is exactly one length unit. In one time unit, the vehicle travels one length unit with respect to ground, the rear (red, left) wheel making exactly one rotation. At the same time, the treadmill surface moves one length unit in the opposite direction with respect to ground. (The yellow arrows indicate the directions of the movement; their lengths are not to scale. The hatching indicates ground. The treadmill is stationary with respect to ground; it does not move.) The question is, how many rotations does the front (right, blue) wheel on the treadmill do, in the same time unit? A) It does not rotate/it slips B) One turn C) Two turns D) Three turns (I would have made this a poll, but I don't have the rights to create one within an existing thread, only if I start a new thread.) To repeat, this is not a trick question; it is a straightforward mechanical detail of the model being discussed. --- End quote --- This is basically just a kinematics question as there are no forces with free spinning wheels. C) Two turns. Can you do the same and answer my multiple choice question. |
| electrodacus:
--- Quote from: fourfathom on February 14, 2023, 03:19:54 pm --- Before we can do that you have to specify if the vehicle is massless, the gears/belts/axles/wheels are frictionless, and if the ice is truly frictionless. Without this information it's impossible to say. Or why don't you tell us? What point are you trying to make? Why don't you simplify, rather than complicate your experiment? --- End quote --- It is a real vehicle so there is friction everywhere. The experiment is setup so that output wheel on ice has much less traction than the input wheel on treadmill so the wheel on treadmill will not slip but the wheel on ice while it still has some friction will be the first to slip of there are forces involved. If it was a frictionless theoretical problem I will have mentioned frictionless surface instead of mentioning ice. |
| PlainName:
--- Quote ---Can you do the same and answer my multiple choice question --- End quote --- What would be the point? If it's not the answer you want you'll just argue the toss about things, and since it's your thought experiment there will be no way to show you are wrong. Even if someone built an actual model of it, you'd still say that something about it is not the same, or you'd 'adjust' your question or even pick a different question entirely. You have form in doing all of those things. |
| electrodacus:
--- Quote from: PlainName on February 14, 2023, 03:47:22 pm --- --- Quote ---Can you do the same and answer my multiple choice question --- End quote --- What would be the point? If it's not the answer you want you'll just argue the toss about things, and since it's your thought experiment there will be no way to show you are wrong. Even if someone built an actual model of it, you'd still say that something about it is not the same, or you'd 'adjust' your question or even pick a different question entirely. You have form in doing all of those things. --- End quote --- It is a testable question. So there can not be any arguments about the correct answer. |
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