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Posted on 11/25/2014 1:21:49 AM PST by LibWhacker
LOL
The effect he is using in his capacitor is the mass-energy equivalence, which comes from the same relativistic derivation, for which E = mc2.
By increasing the charge on the capacitor plates, he is increasing the electric field between them, thus the stored energy in the capacitor (CV2/2, C: capacitance, V: voltage) which amounts to an increase in the "mass" stored in the electric field. By moving the capacitor within the torsion balance, the plates move by differential amounts -- according to his theory -- as the electric field reverses.
It's still a small effect, but it doesn't depend on increasing the mass by actually moving the capacitor. The motion of the capacitor is only used to produce torsional changes to show that a differential force is being produced -- thus an acceleration without reactive mass.
I'm skeptical of the explanation given here. Popular science articles are usually barely worth reading, but I'm distrustful of any article that talks about "increasing the mass" of an object relativistically. Physicists simply do not think in those terms with respect to relativistic effects anymore, and haven't for a very long time. I haven't been a working physicist for thirty years, and it was already out of fashion for at least twenty years when I was still plying the trade.
One has found a way to do that: his name was Moritz Jacobi, when he invented the electric motor in 1834.
It's been in all the papers.
Please ping me to aviation and aerospace articles. Thank you.
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The Bang/Zoom Co-efficient.
Mach 1 is the speed of sound at sea level
No, Mach 1 is the speed of sound, regardless of altitude.
When a gyroscope is spinning, it resists being pushed around because it is interacting with the Earth, the stars, and distant galaxies. If those objects didn't exist, the gyroscope would have no inertia.
No, it resists being pushed around because it has mass (inertia). That doesn't require interaction with other objects.
The Space Studies Institute is championing the cause, inviting tax-deductible donations.
...
It’s safe to stop reading when you get to the above sentence.
You might think, well then, let's restrict our attention to a gas, since the atmosphere is a gas. But... there are different types of gases, including one called an ideal gas, and the rules are different for each of them. Ideal gases do not exist in nature but physicists like them because the calculations are easier and the speed of sound in an ideal gas does not depend on things like temperature, pressure, density, etc. Air is almost an ideal gas, but not quite. So there is actually a variation in the speed of sound in air with different altitudes... For example, check out the following table (from Wiki):
One can even say the speed of sound varies with latitude, as in the following graph:Given normal atmospheric conditions, the temperature, and thus speed of sound, varies with altitude:
Altitude Temperature m·s−1 km·h−1 mph knots Sea level 15 °C (59 °F) 340 1225 761 661 11,000 m−20,000 m
(Cruising altitude of commercial jets,
and first supersonic flight)−57 °C (−70 °F) 295 1062 660 573 29,000 m (Flight of X-43A) −48 °C (−53 °F) 301 1083 673 585
Ignore the information for Titan, Mars and Venus for now, and just concentrate on the graph for the Earth. Notice that the speed of sound is different at various altitudes at the North Pole (dashed line) than at the equator (solid line). I think it has to do with the fact that air is not an ideal gas and that the average temperature at the North Pole is colder (of course) than at the equator, but I'm not sure. Like I said, it's enough to drive a person who is trying to understand this stuff insane!
Regarding your other point. It's a good point and I have a hard time myself believing that my mass sitting here on Earth has anything to do with every little lump of rock clear across the universe. But that is exactly the point of the article. And you have to admit Ernst Mach's point makes you stop and think:
What if there was only one object in the universe? Mach argued that it could not have a velocity, because according to the theory of relativity, you need at least two objects before you can measure their velocity relative to each other... Taking this thought experiment a step further, if an object was alone in the universe, and it had no velocity, it could not have a measurable mass, because mass varies with velocity.
"Mach number is a common 'ratio' unit of speed when one is talking about aircrafts. By definition, Mach number is a ratio of the speed of a body (aircraft) to the speed of sound in the undisturbed medium through which the body is traveling. It is said that the aircraft is flying at Mach 1 if its speed is equal to the speed of sound in air (which is 332 m/s or 1195 km/hr or 717 miles/hour.) An aircraft flying at Mach 2 is flying at twice the speed of sound in air, etc."
http://www.physlink.com/Education/askExperts/ae58.cfm
Now I am confused Mach is a ratio but Mach 1 is an actual speed?
Mach 1 is when the speed is equal to the speed of sound -- a ratio of 1.0-to-1.
okie01 is right, “mach” is a ratio of the actual speed vs. the true air speed of sound under that set of conditions (mostly changes with altitude).
I searched very carefully the entire picture and sequences. I could not, no matter how carefully I looked, find the coffee pot.
btt
I actually thought it was the speed of sound at sea level. How many times have we heard that it was? I know I've heard it many times (including, I think, from some physicists) and just took it at its face value without ever really thinking about it. Mach 1 is a variable that depends on many things but has no meaning unless it's applied to some object or body that's moving through the air (or medium in question). It varies from place to place in the medium, depending on where the moving object is, what the composition, density, temperature and pressure are at that point, etc. You can be flying along at Mach 1 one moment and then the next moment NOT be flying at Mach 1, even though your speed hasn't changed. Thanks for the schooling, guys! :-)
Reactionless drive or not?
[
The center of mass of the piston is actually a point of unstable equilibrium. Theoretically the piston would remain in the middle if it started there if it were a point mass, but even in that case it would not move from the point of unstable equilibrium when the tube is opened or closed to space.
In real life, the piston is not a point mass, and cannot be perfectly balanced, so, like a pencil being balanced on its point it it will leave the point of unstable equilibrium and move toward the end of the tube where the rotational inertia of the piston is greatest. That end of the tube is one of two points of stable equilibrium, and it will remain there as long as the tube spins, vacuum or no vacuum.
]
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