I need a rather clear explanation. Does light have mass?
2007-01-11 12:29:38 · 18 answers · asked by rockability 1 in Science & Mathematics ➔ Physics
No. Light has no mass and it is not matter.
2007-01-11 12:31:30 · answer #1 · answered by Anonymous · 2⤊ 1⤋
Unfortunatly there is no clear explaination. First you have to define mass. Does it have weight?
The idea of photons is that the occur only when light is present, but once the light is off they disappear and have no evidence of ever existing. - Things don't just dissappear. If photons had mass they would remain after the light was off - like water from a hose.
Basically there are a few properties to light that determine the color and brightness.
It's like saying does sound have mass? Well air does, but does sound? No it's vibrations through the air.
Anyways, I don't think it's been proven either way.
2007-01-11 12:36:44 · answer #2 · answered by Curious George 4 · 0⤊ 1⤋
As per the theory of relativity any moving thing has a kinetic energy given by the equation
K.E = increase in mass X C^2.
A moving photon ( light) has kinetic energy. = h n.
where h is planck's constant and n its frequency.
Therefore a photon has an increase in mass of hn/ C^2.
Since the photon's rest mass or mass when at rest is zero.
The final mass of the photon is hn/ C^2.
Any energy is having mass and 1kq mass is 9 x 10^16 joule.
2007-01-11 12:50:41 · answer #3 · answered by Pearlsawme 7 · 0⤊ 1⤋
well I've read in physics, the well known equation of E=mc², E (energy) = (equals) m (mass) c² (in direct proportion to the square of the speed of light in a vacuum).
And now if you reverse the equation you can compair the mass of energy to lightspeed squared. Depending on the ammount of energy, you can work the equation to determine the mass of light. Though light has mass it is still reletive mass. it exist on its own plain, and cannot be measured as that of other forms of mass such as liquids or solids...
so Yes light has mass.
But you cannot measure it. so it cancels out any reletive meaning to light having mass.
all depends on how you look at it.
2007-01-11 12:45:07 · answer #4 · answered by loadsavedelete 1 · 1⤊ 1⤋
Yes it does light is acctually a bunch of energy particles called photons they bounce off of things and the frequency with which they do bounce off creates color. The mass is very tiny BC photons are smal sub atomic particles but yes light does have a very tiny mass.
2007-01-11 12:33:59 · answer #5 · answered by evilive 4 · 0⤊ 2⤋
light has a small amount of mass becuase a black hole such a high gravitational pull that it eve pulls in light... If light has no mass how can light not escape a black hole?
here is a link to a Nasa site on black holes. i find them to be one of the most interesting things i have ever looked into. http://imagine.gsfc.nasa.gov/docs/science/know_l2/black_holes.html
2007-01-11 12:47:50 · answer #6 · answered by Imagantia 1 · 0⤊ 1⤋
no for mass takes up volume, where light just moves around into free areas
2007-01-11 12:33:07 · answer #7 · answered by BigfnD 3 · 1⤊ 1⤋
no the rest mass of a photon is zero, and is mass at any speed is therefore zero. it does posess momentum of hbar / lamboda where hbar is planak's constant over 2 * PI and lamboda is its frequency (of the corresponding wave)
2007-01-11 12:55:29 · answer #8 · answered by walter_b_marvin 5 · 0⤊ 0⤋
Gauge invariance does not allow the photon to have mass!
2007-01-11 14:41:05 · answer #9 · answered by Boehme, J 2 · 1⤊ 0⤋
light has mass...thats it...evrything has mass no matter..hah matter...what is it what so ever...qualls and gluons have mass those are small things of matter that make protons up and hold them together so yes light deff has mass thats why it can be ejected and reflected if no mass than no movement
2007-01-11 12:32:47 · answer #10 · answered by jumanjisapikey 3 · 0⤊ 2⤋