J.C.MacSwell

It is different, but exactly compensated for by the traction force. So effectively no. What do you mean by velocity frame? Frame of reference?

For translational momentum: It is different, but exactly compensated for by the traction force. For Energy: It is different. They have different kinetic energies and they expend different energies. For angular momentum: Less straight forward than the other two above. Just don't think of this as a source of energy, or translational momentum. It is neither.

The traction force reduces the angular momentum of the body without any slipping. It is opposite the force the human applies to the body but is applied at surface level. Please take time and care with your wording. I am often guessing as to exactly what you mean. When a primary braking or accelerating force is applied at the axle, why do you continue to ignore the force of traction that is triggered? It is different for each accelerating or decelerating body depending on the moment of inertia of the body and rate of translational (linear) acceleration/deceleration

I am pretty sure (but I could be wrong) he meant by "Would human gains different momentums to the surface?" to mean transferred momentum to the surface due to the continuous force over the time period. . He is apparently ignoring the forward traction force (a backwards force on the surface) that is triggered by the slowing of the body.

Same force for the human, but the net force is different due to the traction forces being different.

If they have the same mass, then Yes. The one with the greater moment of inertia will go further due to the forward traction force at surface level Yes, the human would transfer more momentum to the surface for the one with the greater moment of inertia: 1. All of the initial momentum Plus 2. All of the additional momentum transferred from the surface to the rolling body due to the forward traction force at surface level However, the second component of the momentum transferred by the human to the surface will be totally offset by the amount transferred to the rolling body by the forward traction force at surface level. So: 1. the net result for momentum will be the same, regardless of moment of inertia, even though the human will exert the same force for a longer time. (again, the greater traction force will have made up the difference) 2. the net result for energy will not be the same, for different of moments of inertia, since the human will exert the same force for a longer distance. (the traction force does not absorb or add energy*) * the traction force does not act through a distance. It is a static force. The very bottom of the wheel is not moving.

What is the nature of the external force? If they have the same external force backwards, opposite the direction of motion, applied say at their centre of gravity, it will trigger a lesser external force forward at ground level. The greater the moment of inertia, the greater this triggered force will be, so the net braking force will be reduced. So the greater the moment of inertia, the greater the kinetic energy, and the further it will go before stopping and the longer it will take. However, the amount of momentum that will be transferred to the ground will be independent of the moment of inertia. Second: If they have the same mass then yes, the centripetal force should be the same.

Absolutely. No problem at all building an anti-gravity device from the same ideas. Just turn the thing at 90 degrees and use the same false assumptions and the same faulty arguments.

How long to lose half it's energy would be easier to define.

That way it would make the answer an infinite amount of time, rather than many, many times that.

It is. Every force has an equal but opposite reactionary force. One could say each is the result of the other (both the force and the reactionary force appear at the same time), but I think it would be more accurate to say they result from buoyancy, pressure differences with depth in the water, or caused by displacement of an equal amount of water as described by Sisyphus.

No slipping? Look at the diagram for diagram #5. What force is slowing the rotation? (hint:there is none) It needs to be corrected. Which site has # 5, and which has #6?

In Figure 5. 1. Force Fr. Where is the equal but opposite force? (Don't just say rolling resistance, that's from an engineering convention to direct it opposite the velocity and at center point, at the axle or hub. That's a simplification/approximation where the difference is not relevant - here it is very relevant) 2. Force N. Here presumably there can be an equal but opposite force on the track due to the proximity of the track but it is directed slightly behind the center point. Is that your intention? (that is OK if it is, but read on) If those are exactly the forces on the wheel, the wheel would decelerate but at the same time accelerate it's rotation, which means it would be slipping. The disc or ring must decelerate it's velocity and decelerate it's rotation in exact proportions in order to not slip. 3. There is a missing force similar to Fr in figure 6. a static friction force forward at track level(and slightly upwards where there is deformation of the track. This force will be greater for a decelerating ring than for a decelerating disc, since it will counteract any tendency for a decelerating wheel to slip (slip backwards, not the frontwards slipping tendency typical in braking) To get it right for a disc or ring freely wheeling on a track with rolling resistance: 1. Get rid of Fr in the location of the center point 2. Force N is OK or can be combined with force Ff below. 3. Add Ff (for friction so as not to confuse it with rolling resistance, or if you prefer Ftr for traction not track), forward at track level and slightly upwards, greater in the case of the ring and lesser in the case of the disc. Or combine it with N The net force from the track to the ring or disc Ftk will be directed ahead of the centerpoint but applied at a point even further ahead of that the wheel is slowed and at the same time the rotation.

Hmm...I'll have to sleep on that one.

The higher moment of inertia allows more kinetic energy available at the same speed, but the total momentum (translational momentum) of the disc and ring are the same. That extra energy must be exerted against something external to the system to change the momentum of the system as a whole. Similarly with angular momentum. That extra energy must be exerted against something external to the system to change the angular momentum of the system as a whole. (in this case the ring has a greater angular momentum than a similar system with a solid disc, but neither system can change without an external force) If you were at rest in outer space you could not change the center of gravity of your system no matter what you do, no matter how much energy you expended to do it. If you spat to the left you would move to the right, leaving your previous rest point behind, but the center of gravity of you and your spit would remain at that point. Your system's momentum would remain at zero in your original rest frame. You could swing your arms and contort in what seems like a spin like manner but your angular momentum would remain at zero as well. You need "outside help" to change either one.

This is good. Also good. (puts your elephants at a slight disadvantage though:D)

No. It does not. If you apply the laws of classical physics exactly, they do not contradict the laws of classical physics. They are consistent with each other. You cannot have an exactly correct model using classical physics laws and prove classical physics laws wrong.

Clearly then by rule #4 you cannot use that definition for "dominant" to define "Top Dog", even if it is "the only definition" (I'm a little skeptical) you know of. That's a reasonable interpretation.

These are very basic classical laws of mechanics. What evidence does not back me up?

Fair enough, Here's my definition. 1. We are currently top Dog. 2. No other species is currently top dog. 3. Top Dog is positive and dominant and most intelligent 4. Positive and dominant and most intelligent must be interpreted so as 1. and 2. are currently true. Still lots of room to interpret that loosely. Have fun. Merged post follows: Consecutive posts merged I've always wondered whether there was a "hive consciousness" as well. An emergence where the whole is greater than the sum of the parts. Oddly, in humans we can have "mob mentality" where we have the opposite affect.

Believe me, angular momentum is conserved as well. Would you believe that the angular momentum is the same for the system, track and ring, at the start, as it is at the end, when the ring comes to a halt? (as well as all points in between)

Hi ABV, I haven't had time to check all this out and respond but if they both roll until they stop, they will both impart the same amount of momentum to the track, even though the ring will roll further. So for the same distance rolled the ring will have imparted less momentum to the track than the disc. (the ring will have more momentum, as the disc slows down more quickly) I realize that may not make sense at a glance but it is true. I looked at the first link and it is interesting. He has applied the rolling resistance as a force at the center point opposite the direction of motion. There is a convention to use it this way in engineering, applying it at axle height to a vehicle. It is a simplification. He then points out additional forces that appear when it is applied in this manner. Nothing wrong with that if he makes sure everything balances out so that the net result is the same.

So currently our only hope for free will is quantum uncertainty (as opposed to just a lack of knowledge), but while that means it might be "free", the "will" might still be an illusion.

I defined it by implication in the opening thread when I declared us currently "top dog". I didn't think a long explanation was needed.

I guess you're right! I heard this some 30 years ago and actually saw the "results" of the flow...or so I thought.