just physics

[rikbe]

Originally posted by RootDBA
Now Gamma radiation is a little different. Firstly, there are no atoms that emit JUST Gamma radiation, it is associated with atoms that also emit one of the other forms or radiation.

Gama waves are electromagnetic waves.
WHat about lasers? they emit electromagnetic waves without other radiation.

[RootDBA]

Lasers work on a completely different principal they radioactive decay. The clue is in the 'Stimulated Emmission' part of LASER- that has nothing to do with radioactivity.

Atoms (such as Argon) are 'excited' causing their electrons to raise to a higher energy level than normal- when the electrons return to their normal state a photon is emitted to discharge this extra energy.

This is entirely different to how gamma radiation is produced,a nd in any case, none of the compounds or elements in Lasers are radioactive.

[rikbe]

Originally posted by RootDBA
Lasers work on a completely different principal they radioactive decay. The clue is in the 'Stimulated Emmission' part of LASER- that has nothing to do with radioactivity.

Atoms (such as Argon) are 'excited' causing their electrons to raise to a higher energy level than normal- when the electrons return to their normal state a photon is emitted to discharge this extra energy.

This is entirely different to how gamma radiation is produced,a nd in any case, none of the compounds or elements in Lasers are radioactive.

I was repling to your statement: there are no atoms that emit JUST Gamma radiation,
In the context of radioactivity, it is correct, as general rule, it is not.

appologies, pressed 'edit' instead of quote

[Edited by RootDBA on 12th January 2004 at 17:24]

[RootDBA]

Originally posted by rikbe

I was repling to your statement: there are no atoms that emit JUST Gamma radiation,
In the context of radioactivity, it is correct, as general rule, it is not.

Justin asked a question about radioactivity not about Lasers, so I would have thought the answer was obvious in this context.

[justin1987]

well, root. u r quite right. i'm sorry for being unable to post earlier. nevertheless, ur answer was quite right.indeed to explain the properties of radioactivity, one has to go to great depths. personally. i have pursued many books on it, (such as resnick and halliday walker) howeverr, i must admit, there is a lot to it than what i had expected.
there is one part, for example, when a question was asked, "after emmiting an alpha particle, (eqivalent to a helium nucleus), the no of protons decrease by one, where as the no. of electrons remain the same. but still, the resultant atom is uncharged. can u tell why?
furthermore, can u prove by stating a chemical reaction that
radioactivity is a nuclear phenomenon?
here's another question:during the course of neutron decay, why does the instability of the atom becomes more pronounced? {ie, why is there a surplus energy in the nucles?}{hint: refer to the nutron -proton ratio}

[justin1987]

well, what happens to the focal length of a convex lens when, a) its centre of curvature increases and when b) its refractive index increases?
hint: refer to lens makers equation