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Anithadhruvbud
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If light is made of particles (particle theory of light), why doesn't it have any mass at all ?
Light is NOT made of what you probably mean when you say "particles". Light is a quantum object that has particle characteristics (but QM particles, not classical particles) if you measure for them and wave characteristics if you measure for them but it is NOT a "particle" OR a "wave", it is a quantum object.Anithadhruvbud said:If light is made of particles (particle theory of light), why doesn't it have any mass at all ?
Anithadhruvbud said:If light is made of particles (particle theory of light), why doesn't it have any mass at all ?
Oh? You want to expand on that?DrStupid said:And light can have mass.
Light isn't made up of photons ?phinds said:Light is NOT made of what you probably mean when you say "particles". .
How can something be without mass ?PeroK said:Who says particles must have mass?
And tell me how ?DrStupid said:And light can have mass.
No, I did not say that. Light IS made of photons but photons are not "particles" as you probably think of them. Please re-read post #2.Anithadhruvbud said:Light isn't made up of photons ?
berkeman said:Please somebody post a link to the FAQ about rest mass and photons (I'm being lazy)...
+1 on that !ZapperZ said:This is why I dislike the current format of the Insight section. It is a PAIN to find an FAQ in there!
Mass is a property, there is absolutely no reason to assume this property must be non zero for all objects. Why would you think it must have mass?Anithadhruvbud said:How can something be without mass ?
I don't know.I think I always find relation between microscopic and macroscopic world.Or maybe because I haven't seen things without mass in my surroundings.Orodruin said:Why would you think it must have mass?
You've probably never seen an electron or a quark either. Do you think they don't exist? The very limited range in which humans evolved makes us TERRIBLE at having any "common sense" regarding quantum mechanics (the very small) and cosmology (the very large).Anithadhruvbud said:I don't know.I think I always find relation between microscopic and macroscopic world.Or maybe because I haven't seen things without mass in my surroundings.
Anithadhruvbud said:I don't know.I think I always find relation between microscopic and macroscopic world.Or maybe because I haven't seen things without mass in my surroundings.
I haven't really thought much about whether light had mass or not.So when I read about it in my textbook,It surprised me.I thought maybe light had very negligble amount of mass as it is made of photons.But It was my fault.I considered photons to be "particles". That was wrong.PeroK said:What about light?
No.The very reason why we have common sense makes us terrible in quantum mechanics.And our common sense is very much dominated by what we see around us.THAT is the problem.These electrons or quarks are just those things that mathematically fits our observations and we agree with it as we trust in mathematics.These atoms are all just the product of human's imagination that correctly fits the logical notion of describing things.But we still cannot really be sure whether these quarks exist or not.It just fits the logical and mathematical theory and we build more on it.phinds said:You've never seen an electron or a quark either. Do you think they don't exist? The very limited range in which humans evolved makes us TERRIBLE at having any "common sense" regarding quantum mechanics (the very small) and cosmology (the very large).
I am sorry.I shouldn't cause people this much pain.I'll search for things in insight section next time.But the thing is I didn't know that insight section existedZapperZ said:This is why I dislike the current format of the Insight section. It is a PAIN to find an FAQ in there!
Zz.
Anithadhruvbud said:And tell me how ?
I don't understand.Can you teach me in high school level?DrStupid said:the mass of the resulting wave is
[itex]m = \sqrt {\frac{{E^2 }}{{c^4 }} - \frac{{p^2 }}{{c^2 }}} = \frac{E}{{c^2 }} \cdot \sin \left( {\frac{\alpha }{2}} \right) [/itex]
Anithadhruvbud said:I don't understand.Can you teach me in high school level?
To me, that is an unreasonable thing to expect. Consider that it may just be beyond high school level - the same way that advanced Calculus and Rocket Science are.Anithadhruvbud said:I don't understand.Can you teach me in high school level?
The particle theory of light, also known as the corpuscular theory, is a scientific model that explains light as a stream of tiny particles called photons. This theory states that light travels in a straight line and can be absorbed, reflected, or transmitted by matter.
The particle theory of light explains that each photon has a certain amount of energy, which is directly proportional to its frequency. This energy gives the photon a mass, as described by Albert Einstein's famous equation, E=mc². Therefore, light has mass in the form of photons.
One of the main pieces of evidence for the particle theory of light is the photoelectric effect, which occurs when light is shone on a metal surface, causing the emission of electrons. This phenomenon can only be explained by the particle nature of light.
The wave theory of light, also known as the electromagnetic theory, explains light as a wave propagating through space. This theory states that light does not have mass because it is not made up of particles. However, both theories are considered valid and have been used to explain different aspects of light.
Yes, light can exhibit both particle and wave-like properties, which is known as wave-particle duality. This means that light can behave as a wave in some situations and as a particle in others, depending on the experimental setup. This phenomenon has been demonstrated through various experiments, including the famous double-slit experiment.