Bender

Let's try a different approach. I might have been too concise for those not familiar with belt design. A belt has a neutral line, which does not change length as the belt goes around a wheel. The length of this neutral line is called the reference length or datum length of the belt. Belt pulleys also have a reference diameter, which is where the reference plane of the belt passes. It is this reference diameter that determines the speed of the belt, and any belt geometry or structure that does not affect the reference diameter, does not affect the belt speed. Adding lugs eg does not alter the reference length of the belt. Regardless of how long the lugs are, the same length of belt is going to pass the belt pulley in a given time. The outer rim of the lugs will move faster, but the belt itself won't. The example given in the animation is a chain. In that case, only the amount of teeth of the sprocket counts and any geometry of the belt is irrelevant. In retrospect, the belt in a snowmobile is most likely a timing belt (synchronous belt or toothed belt), which works like a chain. This means even increasing the thickness does not affect speed. At worst a thick belt would compress the teeth of the belt to the point where they no longer fit the pulley. (Note: tension on the belt will change the length of the reference plane somewhat, but lugs have no influence on this stretching, so no reason to overcomplicate this discussion)

No. The lugs could be touching and still would not be compressing the inner belt because there cannot be tension between them. Are you even considering my answers? I am happy to clarify if you don't understand.

I cannot. In a thicker belt, the outer part compresses the inner part of the belt, resulting in a different speed between the inner part of the belt and the reference plane (middle of the belt if it is homogeneous). This difference only happens at the wheels, and at the flat part, the entire belt moves at the speed of the reference plane, which is the speed of the vehicle. The increase in speed depends thus on the increased diameter of the reference plane. In the case of lugs, sunk into the asphalt or otherwise, no such compression of the inner belt happens, because the lugs are not connected and are free to move away from each other. The radius of the reference plane does not change, and neither does the speed of the reference plane, the speed of the flat part, or the speed of the vehicle.

Now, instead of adding thickness, add lugs of increasing length until you recognise that the speed does not change.

To travel extra distance, the entire flat part would need to slip. It seems unlikely that that would be significant.

The key is to keep slipping, because while slipping, you have kinematic friction, which is significantly lower than static friction. The interesting thing is that while the wheels are slipping in the drive direction, you also have kinematic friction in the lateral direction, allowing the wheels to slip sideways. That is nearly impossible with static friction. Lastly, to keep slipping , it is important to make circle, so the friction force is used for making a circular motion rather than accelerating.

Not really. This would be the case if the belt was only on the wheels, but it is mostly in contact with the ground during the flat part, where belt thickness has no influence on outer belt speed. You would have more slip in front and at the back. There could be some influence because the resistance changes. A higher load usually means the motor will run slower for the same power. Allow me some nitpicking on the figure : those aren't gears, but sprockets or chain wheels.

This looks like it belongs in the homework sections. What precisely is your problem with solving the question?

Tin foil hats are great for cerebral implant protection.

One theory is that it was an evolutionary group advantage to a see where another individual is looking or how he is feeling. Seeing the white helps.

I am not qualified to judge this. If it does work, it would not be unreasonable for Goodenough to want to develop it in secret until it is patentable. A lot of money can be made if the claim is leggit.

The battery has to be charged so even if it works, I see no reason to assume any violation of any laws. At worst its mechanism is misunderstood. If it works. I guess we have to wait for an independent research group to replicate the results.

We're not vaccinating everyone with smallpox, because there is no need . We are vaccinating against diseases that are still around. If it wasn't for stupid anti-vaxxers, we wouldn't need a measles vaccination anymore, because it would have been extinct by now; polio would also be very close to extinction. As long as the anti-vaxxers keep getting their children infected, everyone else needs the vaccinations.

That does not work in space. The ice skater has the ice to push against to start the rotation.

I vote for passing a screwdriver (or anything else which doesn't result in death) behind your back. That way you can easily stop spinning after the pirouette. We just had a thread about absolute rotation. It ended with the assumption that it is possible for spacetime to rotate (as is the case around a spinning black hole) , and as a result it could theoretically be possible to see the stars spinning without your arms moving out. As for the answer to the question what would happen if the universe was spun around you, I think the answer depends on whether all of spacetime is rotating, or only the stuff in it. Then again,I don't think either makes any sense. The latter very quickly encounters speed of light issues. The former is meaningless as nothing would change.

I think it must be this new echo chamber.

Real engineering is quite good.

I did. In the context of this thread, I just wanted to make sure you knew it was a smug, slowly shaking my head, kind of laugh.

I was assuming it was a joke by bible literalists about scientists, in which case it only works if you don't. Perhaps I misinterpreted the context?

Plate tectonics.

As long as you know that every non-bible-literalist is doing a facepalm at level of ignorance this joke requires, we're good

Actually, if in a region the gravitational potential is constant, there is indeed no force. Force is the (negative of) derivative/gradient of potential.

Hmmm, and yet avoiding confusion about his very existence or writing an unambiguous book is beyond his powers.

The rotational energy could increase if the gravitational potential energy decreases (without changing the angular momentum obviously ) . I have not found a conclusive answer to the question how much gravitational potential energy itself adds to the mass/energy. Trouble is that there is no zero reference for potential energy. If you assume an object has the potential to collapse into a singularity, its potential energy becomes infinite. Does anyone have a solution to that?

That is indeed my point. If both are the same, how can one have an effect on spacetime, while the other (suposedly) doesn't?