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The light has mass and weight......

Posted by: JamesHughes - Fri Jul 29, 2011 7:40 am
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The light has mass and weight...... 
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Post Re: The light has weight....   Posted on: Fri Jul 29, 2011 7:40 am
Look up light diffusion.
Look up electromagnetic wave (light) propagation.

Buy a physics textbook.


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Post Re: The light has weight....   Posted on: Mon Aug 01, 2011 7:09 am
If it's attracted by gravity... where does it fall?


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Post Re: The light has weight....   Posted on: Sun Aug 07, 2011 3:29 am
Light does not have mass, light is an electromagnetic wave.
Light does have momentum, which is what might be getting you here.

E=mc^2
P=mv, where v=c, P=mc
m=E/(c^2)
sub m into P=mc
P=E*c/(c^2)=E/c

Momentum of a quanta of light is equal to the energy of the photon divided by its velocity.

However, light still does not have mass, I used the equivalency principle that mass and energy are interchangeable, and light is energy.
Hence, as an energy, can be entered into the momentum equation.

Light can be bent by very large gravitational forces, hence gravitational lensing. But when I say very large, I'm talking stellar-mass-sized. Not Earth-sized (which is pathetically small).

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Why light produces waves, because it weighs. Let us remember that the waves produces a touch.

You are confusing matter waves and energy waves.
Pick up a physics text book and actually read it. Seriously.

Light form some sources does not appear to reach the clouds because the light emmitted from the sources spreads out over the distance.
The intensity of light form a source decreases over distance by the inverse square law.

Do you actually read what anyone says?

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Buy a physics textbook

Do it. Do it now.

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Post Re: The light has weight....   Posted on: Sun Aug 07, 2011 11:36 pm
Photon has energy, it is energy. It is an electromagnetic wave composed of fluctuating electric fields orthogonal to fluctuating magnetic fields which perpetuate each other.

It does not say *anywhere* in that article that photons do not have energy.

It says that the energy of the photon is related to it's frequency. If you actually read the page all the information is right there.

Also: try to keep your scientific faux pas in one thread.

You are confusing mechanical waves, matter waves and energy waves.

Here is a fun website that will help you.
http://library.thinkquest.org/10796/ch8/ch8.htm

http://en.wikipedia.org/wiki/Mechanical_wave


My advice is abandon whatever you currently think you know and start from scratch. Sounds hard, but you've clearly messed up something fundamental when you were attempting to learn, and now you can't grasp this physics.

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Post Re: The light has weight....   Posted on: Mon Aug 08, 2011 11:22 pm
victorespinoza wrote:
If "It is an electromagnetic wave composed of fluctuating electric fields orthogonal to fluctuating magnetic fields that perpetuate between Yes.", then it has weight. Let us remember that the waves are produced by a touch.


There is no logical way that you can get from what I said to your conclusion.
Electromagnetic waves have no mass, they have no weight.
They are energy, not mass.

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Post Re: The light has weight....   Posted on: Tue Aug 09, 2011 4:47 am
...








You're a git, bro.

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Post Re: The light has weight....   Posted on: Tue Aug 09, 2011 3:10 pm
Maybe you should start discussing your ideas with people that speak your language first. Even if we disregard most of the logical problems, some of your statements still do not make any sense whatsoever...

And no, English isn't my first language either.

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Post Re: The light has mass and weight......   Posted on: Fri Dec 30, 2011 3:14 am
Are therw conditions where energy can be made into sub atomic particles?

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Post Re: The light has mass and weight......   Posted on: Fri Dec 30, 2011 1:27 pm
Sigma wrote:
Are therw conditions where energy can be made into sub atomic particles?


Yes that is what a lot of those experiments at CERN are all about creating and studying subatomic particles created from the energy given off by collisions of bits of matter and antimatter accelerated to near light speed.

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Post Re: The light has mass and weight......   Posted on: Sun Jan 01, 2012 5:39 am
Could one maintain x atoms in loop and emit mass with no loss of origjnal atoms? Generation of mass to accelerate would make an energy dependent infinite thruster.

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Post Re: The light has mass and weight......   Posted on: Sun Jan 01, 2012 3:02 pm
No because the collisions that creates the particles destroys the original matter. They get "broken" into their constituent parts as part of the process of decay to energy.

It takes much MUCH more energy to break particles to their elementary sub-particles than could ever be retrieved. There is no free lunch to be had here.

This thread makes even less sense without Adrino's posts in it. I miss him. :lol:


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Post Re: The light has mass and weight......   Posted on: Mon Jan 02, 2012 6:25 pm
What about a means to amplify vacume fluctuations? Can one make a beam of gluons collide with a beam of bosons and mass be emited?

I wonder if through known means energy could be made into mass to use as relitivistic speed propellent? I will try and think of some tests.

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Post Re: The light has mass and weight......   Posted on: Thu Jan 05, 2012 12:12 am
You could build a 'vehicle' that took in solar power and used it to create matter, then accelerated the matter as a thruster.

But it would be incredibly heavy and inefficient, and would create no perceptible thrust in comparison to the sail effect of the ginormous solar panels necessary.


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Post Re: The light has mass and weight......   Posted on: Sat Jan 07, 2012 3:35 am
You don't need mass to propel something, you need momentum (mass times velocity). The law of momentum conservation says that if matter is thrown out the back of a rocket with some momentum, the rocket gains an equal amount of momentum in the opposite direction.

Light does have momentum,* so all you need to do is shine a laser beam in one direction, and you'll accelerate in the other direction.

Of course, this doesn't work so well in practice. This is because you need a lot of energy to produce enough light to propel anything. The equation that relates energy and momentum for light is:

E=pc

where p is momentum and c is the speed of light. If you plug in numbers, you'll find that you need a lot of energy to produce a beam of light with any useful amount of momentum. That's why you don't fall over when you fire up your laser pointer.

I'm certain that people have thought of doing propulsion using high intensity lasers, but I would suspect that it would be highly impractical with today's technology.

--

*You might ask how light can have momentum, given that momentum is defined as mass times velocity. In the case of massless matter like light, we make an exception and define momentum (for a photon) as p=h/l, where h is Planck's constant, and l is the length (if you're skeptical, check the units).


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Post Re: The light has mass and weight......   Posted on: Mon Jan 09, 2012 7:59 pm
Solar sails work by being pushed by light. http://en.wikipedia.org/wiki/Solar_sail

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