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Everything posted by J.C.MacSwell
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I assumed his question was wrt the spinning disc in the OP, and for the simplest cases of uniform mainstream flow, the answer is fairly straightforward. There would be both lift and drag, except in the case of the main flow parallel to the axis of the disc and spin, in which case there would be just drag (oscillations from vortex shedding not withstanding but lift should average zero) It can certainly get complicated beyond that.
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If there was flow in the main stream relative to the spinning disc in any direction except parallel to the axis of the disc, then yes
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Relativistic mass, Gravity and Dark matter.
J.C.MacSwell replied to psynapse's topic in Modern and Theoretical Physics
I wish I could answer that precisely. I don't think we really know what mass is. Rest mass has well known effects in it's frame and of course effects in other frames that must be consistent with that. -
Why is anti-matter so expensive?
J.C.MacSwell replied to Akpolarbears's topic in Modern and Theoretical Physics
This reminds me of the old joke on being handed a ticket "70 miles/hour...but officer I haven't even been driving for an hour!" -
Relativistic mass, Gravity and Dark matter.
J.C.MacSwell replied to psynapse's topic in Modern and Theoretical Physics
Does an object which spins gain mass due to kinetic energy? Yes. It is energy within a bound system. It adds to the rest mass of the object. Can relativistic mass cause gravity? As per above example yes, but generally not and/or misunderstood. Some kind of emergent property of interplay between mass, kinetic energy and gravity...(well stated) but I don't believe that is enough to account for dark matter and likely is a small effect that has already been taken into account -
Now I know why my radiant heater always frosts up in the garage...I wired the outlet wrong
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1) not necessarily (only if by coincidence or design) After no longer in contact, aerodynamics aside, the c.g should follow a parabolic path 2)It could do that, if the timing, velocity ,angular moment and pitch orientation at take off are just right, and the landing ramp properly positioned and angled
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Fluid would be drawn toward the centre of the disc from either side, and outward and in the direction of rotation along the surface and outer edge. This flow would effectively stop the Reynolds number from increasing without limit (by limiting the effective length, which can be chosen arbitrarily for the equation) and continuously increasing turbulence...so it would either fluctuate in some manner or approach a constant state depending on whether it was shedding vortices or not.
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Is there a force of interaction between energy?
J.C.MacSwell replied to pritikamehra's topic in Relativity
As much of a question as a statement...but from that perspective are not all known forces interactions between energies? -
Fair enough, but in an absolute sense, for any and every inertial frame extended without limits, momentum is conserved...correct?
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The context in this case with the topic at hand was perfect. I tried to google it but found nothing.
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That's brilliant! (no pun intended)
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The stiffness of the materials, and glue, come into effect, as well as the distribution of the forces that make up 50N net force. If, for instance, the 50N was all in that location and the blue material flexible enough, it would peel off, especially if the glue and board were rigid as it would limit the spreading of the load and concentrate it where the peeling was taking place. The higher numbers calculated would only be true if the whole area failed at once (In peel it could seem instantaneous, but it would not be)
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Distinguishing between acceleration and gravity
J.C.MacSwell replied to skeptic1's topic in Relativity
Tidal forces and frame choosing aside, it would be more accurate saying gravity is equivalent to inertia, and resisting gravity is equivalent to acceleration (being accelerated). -
Best material to absorb heat and then slowly radiate that heat
J.C.MacSwell replied to parsson's topic in Physics
Sodium Sulphate: from http://en.wikipedia.org/wiki/Sodium_sulfate The high heat storage capacity in the phase change from solid to liquid, and the advantageous phase change temperature of 32 °C (90 °F) makes this material especially appropriate for storing low grade solar heat for later release in space heating applications. In some applications the material is incorporated into thermal tiles that are placed in an attic space while in other applications the salt is incorporated into cells surrounded by solar–heated water. The phase change allows a substantial reduction in the mass of the material required for effective heat storage (the heat of fusion of sodium sulfate decahydrate is 25.53 kJ/mol or 252 kJ/kg[19]), with the further advantage of a consistency of temperature as long as sufficient material in the appropriate phase is available. -
[thermodynamics] basic steady state tasks
J.C.MacSwell replied to tomek888's topic in Classical Physics
Don't assume it if is water at 32 and 37 F. You would be wrong. -
For the OP... Generally speaking the light rays that enter your eye did not "start off at your eyeball".
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Don't do it. I gave him my money in 2015 and he didn't come through. I had to get help from other sources, so don't make the same mistake I did and trust this guy. edit: I think I fell for the "Pure Genius" moniker, obviously very clever but now (and as it turned out, in the future as well) I'm a little more skeptical...
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If you love something set it free, if it loves you it will come back, if it does not...hunt it down and kill it
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Factors affecting Coefficient Of Lift?
J.C.MacSwell replied to Endercreeper01's topic in Classical Physics
Stall http://en.wikipedia.org/wiki/Stall_(flight) -
Jim is not always honest and a little devious...but not malicious...also doesn't own a gun
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Clearly Bigfoot is Camera shy, with the lack of extra sightings with the increased carrying of cameras... ...smart though...avoiding getting killed crossing busy highways... ...but very friendly, getting along extremely well with black bears if not humans... Here is one photographed at a party with my cousin Jim... This may contradict what I said earlier about being camera shy but Jim had told him a number of black bears were coming to the party (he actually didn't invite any)
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Not very well...while in orbit/freefall...
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Well...those small figures represent a lot of energy per kg. Compare it with wood, oil or propane. If it really was safe it would be worthwhile.