electromagnetic waves and photons (power, light and heat)?

Question

am i right in assuming that
1.) light, heat, radio waves, and power are all the same kind of thing. and converting electricity to heat, x-rays, or light is simply changing the frequency of the same thing.
2.) wavelengths of gamma are the result of the decay of certain radioactive elements
3.) heat, x-rays, Am radio, ect.. are all photons?
Also do photons have mass?
And i heard that light has been succesfully stopped, yet when it returned to a vaccum it's speed immediately went to 3*10^8 meters per second is this true?

Answer 1

Wow, this one is a bit involved!

1. light, RADIANT heat (not conducted or convected through metal or water for example) and radio waves are all indeed frequencies of electro-magnetic radiation. Not too sure what you meant by power, so I've left that one out for the time being.

2. Gamma rays are indeed also electro-magnetic radiation. Very high energy, but yes! Gamma rays come from radio-active decay of certain elements yes.

3. Radiant heat, X-Rays, AM Radio waves can also be considered to be photons yes. They are normally considered as waves, but E-M Radiation can appear to be both a wave or a particle (called "Wave-Particle Duality").

4. Photons have energy and energy and mass are different forms of the same thing (from the famous E = M.C^2 equation). So a photon might be thought to have mass - But it doesn't. The reason is that we have to refer to the REST MASS of a photon. If you stop a photon, it has no energy (mass), so a photon is considered massless as it only has energy while moving.

5. Photons have been stopped and indeed, when released, they resume their normal speed in that medium.

I hope that helps a little?!

Answer 2

As soon as you turn off the led, the existing light waves would continue bouncing around in the jar. Each time they bounce, they would lose a portion of their amplitude, because theyd be absorbed byt the surface material of the jar But given the speed of light, this would happen so quickly that it appears to the human eye that the light just disappears as soon as the led is turned off.

Answer 3

Take a look at

http://www.physorg.com/news6123.html

Answer 4

in one very important way everything has the same common basis, energy.

Answer 5

study up more on photons