What period would it take say to have a pound of photons? Apology if its a silly doubt
2006-08-11 01:48:16 · 10 answers · asked by dart 1 in Science & Mathematics ➔ Earth Sciences & Geology
Photons do have a mass - but no rest mass. One can arrive at a weight only if there is a rest mass
2006-08-11 01:55:17 · answer #1 · answered by spice 5 · 0⤊ 1⤋
Weight Of A Photon
2017-01-18 06:02:20 · answer #2 · answered by oberlin 4 · 0⤊ 0⤋
As others have said, the photon has no rest mass, but it does have a relativistic mass, m=E/c^2, where c is the speed of light and E is the photon's energy, which can be computed by Planks equation
E = hf
where f is the photons frequency and h is Planck's constant, 6E-34 Js.
For example, ordinary visible light is around 500 nm, corresponding to a frequency of 6E14 Hz, or an energy of 1E-20 J. Thus the mass of a 500 nm photon is 1.1E-37 kg, or 0.00000000000000000
000000000000000011 gram.
2006-08-11 02:32:31 · answer #3 · answered by helene_thygesen 4 · 2⤊ 0⤋
L = photon wavelength
L = 5E-7 meters (visible light)
f = photon frequency
c = speed of light ~ 3E8 m/s
f = c / L = 6E+14 Hz
E = photon energy
h = Planck's constant ~ 6.626E-34 J s
E = hf = 3.9756E-19 J
m = equivalent mass
m = E / c^2 = 4.417E-36 kg
1 kilogram = 2.2046 pounds
It would take about 1E35 visible light photons to make a pound of mass.
(However, photons of visible light don't engage in pair production. You need photons with energy above ~1 MeV as a requirement for changing the radiation into matter.)
2006-08-11 03:26:31 · answer #4 · answered by David S 5 · 2⤊ 0⤋
Photons are massless according to the Standard Model. The best expermentally measured upper level for the mass is about 10^-51 gram.
2006-08-11 02:03:15 · answer #5 · answered by cordefr 7 · 1⤊ 0⤋
1. Light is not made of photons. Thats like saying a person is made of humans.
A photon is the 'particle form' of light. Quantum physics says that things appear to be something depending on how you observe them. If you observe light in certain ways it acts like a particle. We call light in this context a photon.
2. Photons are massless.
2006-08-11 01:59:42 · answer #6 · answered by Anonymous · 0⤊ 1⤋
Photons have no mass. Therefore, photons have no weight,
2006-08-11 01:53:45 · answer #7 · answered by Anonymous · 0⤊ 1⤋
Photons are massless
2006-08-11 01:55:46 · answer #8 · answered by MadMaxx 5 · 0⤊ 1⤋
photons have zero mass.... so you'd need a little bit more than infinity to get a pound.
2006-08-11 01:54:10 · answer #9 · answered by scruffy 5 · 0⤊ 1⤋
photons are massless... they do not have a rest mass
2006-08-11 05:42:55 · answer #10 · answered by vedz666 3 · 0⤊ 1⤋