Does light or radio waves have mass?
- Thread starter wwillson
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photons have no "rest mass," but they do have momentum. it's part of the wave-particle duality.
but essentially, e-m waves (light) have no mass, no.
-michael
but essentially, e-m waves (light) have no mass, no.
-michael
How can something have no "rest mass", but have momentum? Seems like a contradiction?
Welcome to the Quantum world!
Welcome to the Quantum world!
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The theory behind photon mass is that in order to measure the mass you have to stop the photon to measure it. If you stop a photon then the photon will no longer exist. Therefore, it is impossible to actually measure the mass of a photon. However, there are many other ways to compute such numbers which relate directly to energy production and absorption. The Compton effect is based on the total absorption of photon energy and is one mathematical formula used.
Bob, Get out your bottle of Excederin and cogitate on this for awhile. It's been about 35 years since I went through those equations, so would can't say I have a good feel for them anymore.
http://www.phys.virginia.edu/classes/252/energy_p_reln.html
Don't Quantum mechanics fix old Volkswagens?
The Compton effect is that if you are driving your white *ss through Compton after dark and come stop moving, you will cease to exist.
if i remember right from a class a long time ago they are influenced by gravity, does that indicate some sort of mass?
MolaKule
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Recall that momentum p = mv, or mass x velocity. For a photon, the mass being spoken of here in "inertial" mass, not rest mass. Inertial mass is that equivalent mass of an object due to its inertia.
Photons don't have normal rest masses as does a car for example.
Photons can actually impart momentum, radiation pressure, and resulting forces. Out in space, you can make a Space Sail that is propelled by radiation pressure from photons from the Sun.
Duality?
Welcome to the amazing world of quantum physics and then wonderful wave-particle theory.
I may act like both...but only one behavior at a time
Professor Einstein's word on quantum physics, "spooky"
Welcome to the amazing world of quantum physics and then wonderful wave-particle theory.
I may act like both...but only one behavior at a time
Professor Einstein's word on quantum physics, "spooky"
I thought they fixed broken computer hard drives...
Shannon,
Although I am weak in organic chemistry the buckbeyball molecule is one crazy thing.
I had enough hard time dealing with cyclohexane's conformations (axial v. equatorial hydrogen) chair vs. boat and everything else *lol*
Steric Strain alone I am surprised they actually put a buckeyball together.
Although I am weak in organic chemistry the buckbeyball molecule is one crazy thing.
I had enough hard time dealing with cyclohexane's conformations (axial v. equatorial hydrogen) chair vs. boat and everything else *lol*
Steric Strain alone I am surprised they actually put a buckeyball together.
I thought he called it "spooky at a distance" with respect to the wave particle duality.quote:
Originally posted by outrun:
Duality?
Welcome to the amazing world of quantum physics and then wonderful wave-particle theory.
I may act like both...but only one behavior at a time
Professor Einstein's word on quantum physics, "spooky"
Can anyone explain or point me to an article or research paper proving or explaining why object has a mass. In all my years of taking physics I have never heard that anyone could explain why do objects have mass and what mass actually is. Not weight, but mass.
Regards,
Regards,
MolaKule
Staff member
Here is an analogy that might help:
Two electrostatic particles of different signs of charge have a force of attraction between each other because they create a field around themselves (the electric field E). This field is the "intelligence" that tells one particle that another particle is somewhere in space.
Likewise, a mass is the charcteristic of an object such that it sets up a gravitational field which provides a force to attract another mass.
A force in both cases is defined as an interaction that causes one body to accelerate toward another. And acceleration of course, is the rate of change in velocity of an object.
Two electrostatic particles of different signs of charge have a force of attraction between each other because they create a field around themselves (the electric field E). This field is the "intelligence" that tells one particle that another particle is somewhere in space.
Likewise, a mass is the charcteristic of an object such that it sets up a gravitational field which provides a force to attract another mass.
A force in both cases is defined as an interaction that causes one body to accelerate toward another. And acceleration of course, is the rate of change in velocity of an object.
Outrun:
Those Organic I chair,boat,twistboat conformations are a PITA.
Hopefully next semester when I take Quantum Theory i'll be able to answer this photon question.
Those Organic I chair,boat,twistboat conformations are a PITA.
Hopefully next semester when I take Quantum Theory i'll be able to answer this photon question.
We are only a figment of our imaginations. Nothing is real.
MoleKule, as I understand: electric charge is just a presence or absence of extra electrons. What is mass? Is it a presence of some additional matter? If yes, then some latest research into anti-matter (or dark matter) might be onto something. On the other hand if the answer is still yes, we have much more questions than answers. What actually defines this matter and its properties? Electric charge can be transferred, is it also the case with mass-matter-energy case? Black holes, in theory, have no real (as we define it usually) matter whatsoever, yet they have mass and electric charge. What happens at this point? Does matter gets transferred into its original state? Does it become a pure mass without any real physical properties? Or it does have some very specific properties without original representation? This topic is very interesting, yet confusing for the lack of knowledge. If you or someone else can shine some light onto it I would be very grateful.
Regards,
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