Taking a Fresh Look at the Physics of Radiometers.
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From: NoEinstein on 9 Jun 2010 16:48 On Jun 8, 2:04 pm, Sam Wormley <sworml...(a)gmail.com> wrote: > Sam: Any teacher who grades papers with an erroneous "check" sheet, is the one who is... OUT. The status quo won't cut it in science any more! NoEinstein > > On 6/8/10 5:40 AM, NoEinstein wrote: > > > Photons are emitted by all masses whether charged or not. > > Strike 1 > > 2. Photons propogate at 'c' plus or minus the velocity of the source. > > Strike 2 > > 3. Photons are absorbed by all masses whether charged or not > > Strike 3 > > Yer Out!
From: NoEinstein on 9 Jun 2010 16:59 On Jun 8, 3:00 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > Dear Timo: Your mistake, fellow, is to keep swinging away after the last out in the 9th and final inning. The correct formula for kinetic energy is my own: KE = a/g (m) + v / 32.174 (m). The correct momentum equation is: F = v / 32.174 (m). Both of those have the units of force be in pounds. The only difference between the two is that the KE INCLUDES the static weight of the dropped object from the get-go of the fall. My equation exactly predicts the height of drop to cause a lighter clovis pin to impact a larger clovis pin (head-to-head) with a KE that matches the INERTIA (weight) of the larger pin. When that happens, the pins will stay in contact so long that the ringing sound gets dampened to a THUNK. Recordings of the impact sounds caused by various height drops verifies my equation. NoEinstein > > On Jun 8, 9:34 pm, "Tim BandTech.com" <tttppp...(a)yahoo.com> wrote: > > > On Jun 8, 2:30 am, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > > On Mon, 7 Jun 2010, Tim BandTech.com wrote: > > > > On Jun 7, 3:55 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > > [a very quick point, will return later] > > > > > > Of course the energy hasn't disappeared! Momentum isn't energy, energy > > > > > isn't momentum! They're not the same thing! > > > > > When the momentum is absorbed is not the energy likewise absorbed? > > > > No! (I think "absorbed" is the wrong word here.) > > > Is this your new careful use of language Timo? This 'no' is to mean > > that you wish to discuss the reflected case. Well, I am discussing the > > absorbed case. So please do not change the argument as a means of > > falsifying my argument. > > So, be clear! We have been discussing the case of reflection as well, > not just absorption. If you're restricting yourself here to absorption > only, say so. > > In the reflecting case, there can be a transfer of momentum with no > transfer of energy. You can have transfer of momentum without > absorbing the photon. If you absorb the photon, yes, you transfer all > of the momentum and energy. Most of the energy (all of the energy, for > a stationary absorber) _doesn't_ become work done on the absorber. > > This is the next step (2a,b) in the other line of this thread, let us > deal with it there. > > > This 'No' above can be miscontrued. I will > > take this wording as support of my argument, for there is no actual > > falsification content provided here. > > That's very sloppy. A lack of falsification is not support (for > example, a complete lack of comment is also a complete lack of > support). > > > > > > Bounce a ball off a wall. KE_in = KE_out. No loss of KE. Change in > > > momentum = 2 * momentum_in.- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text -
From: NoEinstein on 9 Jun 2010 17:09 On Jun 8, 5:05 pm, "k...(a)nventure.com" <k...(a)nventure.com> wrote: > On Jun 8, 10:19 am, Sam Wormley <sworml...(a)gmail.com> wrote: > > > On 6/8/10 3:50 AM, k...(a)nventure.com wrote: > > > > While Einstein's Special Relativity is consistent in itself, it is > > > not without its problems. > > > > And your second sentence is wrong. > > > > The Eotvos experiment by R. H. Dicke at Princeton demonstrated > > > that mass is not relativistic. > > > > Furthermore, there is the twin paradox. > > > And just how do you see the "twin paradox" as a problem for > > special relativity? Be specific. > > I thought I was. Anyway, a paradox is a self contradictory statement. > > Special Relativity maintains that: > > 1. There is no preferred frame of reference (FOR), so any FOR is > just as valid as any other. So the FOR of the traveling twin is > just as valid as the FOR of the stay at home twin. True > 2. Time contracts, only contracts, and always contracts, when moving > near the velocity of light. There is no variation in REAL time due to velocity. But CLOCKS of all kinds are slowed by the front-to-back ether pressure associated with high speed travel in space. > 3. Nature is time symmetrical. What the hell does THAT mean? > > So: > > 1. The traveling twin grows old slower (due to time contraction) > than does the stay at home twin, and They both age identically. The traveling twin gets to see... the future, because he's been gone for "that" long. > 2. The stay at home twin grows old slower than the traveling twin > (due to time contraction) concurrently (i.e., at the same time) > because the FOR of one is just as valid as that of the other. The traveling twin ages slower because his or her body is pressed by more flowing ether. That twin would also be more sluggish from the pressure. > > Therefore: > > Each twin is younger than his/her sibling when the traveling twin > completes his/her trip and they are again together at home, and at > rest (stationary) in the 'stationary system'. The same real age, Dummy. Depending upon the environment (smoking, etc.), each twin can look different upon reuniting. > So is this not a contradiction? and > > So is this not a problem within relativity? > > That's why I specificly asked: "Which twin is younger that his/her > sibling when they are both together and at rest in the 'stationary > system'?" > > D.Y.K.
From: NoEinstein on 9 Jun 2010 17:12 On Jun 8, 5:36 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > Dear Timo: "The truthfulness of any scientific theory is inversely proportional to the time required to explain it." So, yours doesn't hold water! NoEinstein > > On Jun 8, 8:26 pm, Timo Nieminen <t...(a)physics.uq.edu.au> wrote: > > > Next will be: 2a. Absorption by a stationary absorber, and 2b. > > Absorption by a moving absorber. > > To continue: > > 2a. Stationary absorber. > > (i) Classical particle. > > E_in = E = (1/2)mv^2, > E_out = 0, > p_in = mv = 2E/v, > p_out = 0. > > I = mv = 2E/v, > F = mvN = 2EN/v. > > The force is 1/2 of the force on a reflecting plate. > > Since there is no motion of the reflector, no work is done. So, E_in > becomes energy other than mechanical energy. part from losses due to > acoustic waves (in the air and the plate) which are potentially lost > from the plate/particle system, this energy will result in heating of > the reflecting plate (+ the particle that is now stuck to it). > > So, rate at which the plate is heated is EN. > > (ii) Photon. > > E_in = E = hf, > E_out = 0, > p_in = h/lambda = E/c, > p_out = 0. > > I = h/lambda = E/c, > F = hN/lambda = EN/c. > > The force is 1/2 of the force on a reflecting plate. > > Again, no work, so all of this energy goes to heat the plate, at a > power of EN. > > (iii) Classical wave. > > P_in = P0 > P_out = 0 > > Without assuming a particular momentum, all we have is that no work is > done, so the heating power is P0. Since no work is done, we don't have > any information about the force yet. > > 2b. Moving absorber, moving at v_cs (as before, just a change to a > moving coordinate system). > > (i) classical particle. > > E_in = (1/2)m(v+v_cs)^2, > E_out = (1/2)m v_cs^2, > p_in = m(v +v_cs), > p_out = m v_cs. > > E_in - E_out = (1/2)mv^2 + m v v_cs = E + m v v_cs > > I = p_in - p_out = mv = 2E/v, as for stationary absorber. > F = mvN = 2EN/v, as for stationary absorber. > > The rate of energy transfer to the absorber is: > > (E_in - E_out)N = EN + m v v_cs N = heating power + m v v_cs N > > (since the heating power must be unaffected by our change in > coordinate system). > > The remainder of the power transfer must be the rate of doing work, > which gives us the force by > > F = P/v = m v v_cs N / v_cs = mvN = 2EN/v, as for the stationary > absorber. > > For v_cs << v, almost all of the incident kinetic energy goes towards > heating the absorber, not doing work on the absorber. > > (ii) Photon. Blueshifted by (1+v_cs/c). > > E_in = E(1+v_cs/c) = hf(1+v_cs/c), > E_out = ?, > p_in = h(1+v_cs/c)/lambda = E(1+v_cs/c)/c, > p_out = ?. > > We don't end up with a photon anymore. With the particle sticking to > the plate, the particle still had KE and momentum when it was stuck to > a moving absorber. > > If we assume that E_out = 0, p_out = 0, we have > > Rate of transfer of energy = E_in N = heating power + hfN v_cs/c = > heating power + EN v_cs/c > The leftover power, beyond the heating, must be the rate of doing work > on the absorber. So, > > F = power/v = EN v_cs/(c v_cs) = EN/c, the same as for the stationary > absorber. > > (p_in - p_out)N = F + EN v_cs/c^2 > > So, the momentum of the absorber is increasing, by an extra amount. We > could have assumed that P_out was zero for the classical particle > case, and we would have gotten the same result. In the particle case, > the increase in momentum is due to the increase in mass (still moving > at v_cs) due to the particles sticking to the absorber. > > Here, we are increasing the inertia of the absorber (I will just call > it "inertia", to not need to bring definitions of mass, relativistic > mass, rest mass, etc into it, especially since we still being > classical.) > > The rate of increase of inertia is (rate of extra increase in > momentum)/v_cs = EN/c^2, = heating power/c^2. So, the thermal energy > we are adding to the absorber has inertia E/c^2. > > (iii) Classical wave. Blueshifted by (1+v_cs/v_w). > > P_in = P0(1+v_cs/v_w) > P_out = 0? > > Rate of heating ust be the same as in the coordinate system where the > absorber was stationary. > > Rate of transfer of energy = rate of heating + rate of doing work > P_in - P_out = P0(1+v_cs/v_w) = rate of heating + P0 v_cs/v_w > > F = P/v = P0 v_cs/(v_w v_cs) = P0/v_w. This is the radiation pressure > force, half of what we had for the reflector. > > From the reflecting case, we had > > momentum flux = p_flux = P0/v_w. > > Here, we have p_flux = P0(1+v_cs/v_w)/v_w = force + extra increase in > momentum. > > Rate of increase of inertia = extra increase in momentum / v_cs = P0/ > v_w^2. > > 3. In summary, > > The momentum flux of a classical wave of power P and speed v_w is > p_flux = P/v_w. > > The force exerted on a reflector is 2 p_flux = 2P/v_w. > > The force exerted on an absorber is p_flux = P/v_w. > > For a stationary reflector, no energy is absorbed; there is no > heating. For a moving reflector, there is a change in energy of the > wave due to redshift/blueshift; this is the work done on the reflector > and there is no heating. > > For an absorber, moving or stationary, there is heating. For a moving > absorber, some of the energy goes into work done on the absorber, the > rest is heating. For v << v_w, most of the energy does into heating. > > For the wave or photon, it's almost the same as the case for the > classical particle. There are two main differences: > > (i) The energy-momentum relationship is different for the classical > particle; the classical particle stream exerts twice as much force. > > (ii) Energy has inertia. > > Arguments against the existence of radiation pressure/force/momentum > based on the ratio of momentum to energy, or work done to heating, > apply (almost) equally to the classical particle case - the numbers > are the same except for a factor of 2. > > Anyway, this is the simple theoretical framework. The key result, > 1b(iii), is sufficient to show that a wave has momentum, which is > sufficient to show that it will exert a force if reflected, refracted, > or absorbed. 2a,b show that this is all consistent with absorption of > energy and heating.
From: NoEinstein on 9 Jun 2010 17:15
On Jun 8, 7:00 pm, Sam Wormley <sworml...(a)gmail.com> wrote: > Dear Sam: People who discuss "frames"... 1. Have difficulty visualizing physical relationships; and 2. Don't know that Einstein's SR theory has been disproved by yours truly! NoEinstein > > On 6/8/10 4:05 PM, k...(a)nventure.com wrote: > > > On Jun 8, 10:19 am, Sam Wormley<sworml...(a)gmail.com> wrote: > >> On 6/8/10 3:50 AM, k...(a)nventure.com wrote: > > >>> While Einstein's Special Relativity is consistent in itself, it is > >>> not without its problems. > > >>> And your second sentence is wrong. > > >>> The Eotvos experiment by R. H. Dicke at Princeton demonstrated > >>> that mass is not relativistic. > > >>> Furthermore, there is the twin paradox. > > >> And just how do you see the "twin paradox" as a problem for > >> special relativity? Be specific. > > > I thought I was. Anyway, a paradox is a self contradictory statement. > > > Special Relativity maintains that: > > > 1. There is no preferred frame of reference (FOR), so any FOR is > > just as valid as any other. So the FOR of the traveling twin is > > just as valid as the FOR of the stay at home twin. > > 2. Time contracts, only contracts, and always contracts, when moving > > near the velocity of light. > > 3. Nature is time symmetrical. > > > So: > > > 1. The traveling twin grows old slower (due to time contraction) > > than does the stay at home twin, and > > 2. The stay at home twin grows old slower than the traveling twin > > (due to time contraction) concurrently (i.e., at the same time) > > because the FOR of one is just as valid as that of the other. > > > Therefore: > > > Each twin is younger than his/her sibling when the traveling twin > > completes his/her trip and they are again together at home, and at > > rest (stationary) in the 'stationary system'. > > > So is this not a contradiction? and > > > So is this not a problem within relativity? > > > That's why I specificly asked: "Which twin is younger that his/her > > sibling when they are both together and at rest in the 'stationary > > system'?" > > > D.Y.K. > > Do you understand that the frames of the twins are not both > inertial frames of reference? > > Physics FAQ: The Twin Paradox > > http://math.ucr.edu/home/baez/physics/Relativity/SR/TwinParadox/twin_...- Hide quoted text - > > - Show quoted text - |