Jonathan wrote:
Rest masses are not known to change under any circumstances, which is why they are listed in tables of particle properties.
Well, in the later literature of relativity theory, the rest mass of an object was referred to as the "invariant mass", however I do not think this meant that it could not change in value. By "invariant", physicists were trying to imply that the rest mass was not observer dependent. In other words, every outside observer, regardless of the state of motion of his reference frame with respect to the object, would measure the same rest mass for it. If that rest mass underwent a change in value, however, then all of the outside observers would measure the
same change.
Anyway, I think in my "...Update" thread on the Community Buzz forum I reproduced a calculation that showed how a metal weight falling from infinity to the Earth's surface would, indeed, lose a minute portion of its rest mass in the process as that mass was converted into the kinetic energy that the object displayed.
The subjects of relativity theory and quantum physics can certainly be difficult to study and lead to some confusion. From what studying of these topics I have done, I learned that wherever one has energy, one has mass and wherever one has mass one has energy. From this it follows that when one extracts energy from a system that system must lose some of its mass. And, whenever one adds energy to a system, that system must gain some mass.
Ordinarily, the changes in mass associated with a change in the energy content of an object are so minute that we can ignore them in most calculations. For example, when one, say, compresses a spring, that spring's energy content is raised and it does
gain a slight amount of mass. On the other hand, when a nuclear reaction takes place that releases energy into the environment, one will find that the masses of the nuclear products formed will be slightly less than the masses of the nuclear reactants before the reaction takes place. I think I read somewhere that when an atomic bomb detonates, about 1/10th of 1% of the critical mass of its U235 is lost and converted into gamma radiation which then stimulates the air around the detonation to emit the many other forms of electromagnetic radiation the blast creates.
When Gene states:
The Bessler wheel was a 'simple' mechanical device that was powered by nothing more than gravity.
I can agree with the first part...the wheel was "simple". However, I think it is confusing to say that the device was "powered" by gravity. That implies that gravity is somehow the "fuel" that Bessler's wheels used. I like to think that a gravity wheel's weights depend upon the presence of a local gravity field (with the proper orientation with respect to the weights) in order to allow the wheel's mechanisms to slowly, but continuously, convert the rest masses of the device's weights into the kinetic energy that the wheel displays and which it can output to its environment to perform useful work.
ken
On 7/6/06, I found, in any overbalanced gravity wheel with rotation rate, ω, axle to CG distance d, and CG dip angle φ, the average vertical velocity of its drive weights is downward and given by:
Vaver = -2(√2)πdωcosφ
