Well I have my own theory, which is probably wrong, but nevertheless its just a theory that i've come up with by researching this in some detail...Please anyone who does physics at uni/school tell me if I'm right
Basically the problem of the Black body curves was that they should have got steeper and steeper towards the shorter wavelengths. There are a few reasons for this. Quite simply it was thought that if you increased the temperature of a black body then it should radiate energy at higher and higher frequencies, until it raidated an infinite amount towards the UV end of the spectrum. Why? If you know what a standing wave pattern is (it's similar to a wave you make with a rope held at both ends) then it helps.
A black body accepts radiation only if they are in standing wave patterns. At larger wavelengths, there are less possible patterns of standing waves than at shorter wavelengths. These are called "modes" - there are many more modes of waves of higher frequencies than of lower frequencies. So it makes sense to beleive that the Black body sohudl be able to absorb and emit many more modes of higher frequency radiation, doesnt it? (because there are so many more patterns of standing waves possible)...But this DID NOT occur - the graph reached a peak and dropped off. Classical physics said that there should not be a peak.
This was not able to be explained at the time until Planck applied some of his skills as a mathematician (he was an expert at statistics apprently) to the black body curves and he came up with a formula that worked. The problem with the formula was that it assumed that light came in particles, or quanta each with energy E=hf, not waves....so he was making a bold assumption. Anyway, people realised that it was not only light but also the energy levels of the electrons that were quantised. This solved the mystery and explained the curve, and explained why the UV catastrophe didnt occur. How? Well, when a black body begins to cool and emit radiation, it does so in packets. Since E=hf, it would not be able to emit much radiation of the higher frequencies because (1) there is not enough energy to push the electrons to an energy level where this is possible, because remember, its "all or nothing" - they either have the energy, or they dont, so they get stuck at an energy level below it and emit radiation of a lower frequency and (2) the energy from each photon is tremendously high, since f is high in the formula E=hf so you would expect fewer photons. Simiarly you would expect a lower number of photons from the longer wavelengths because there's not a lot of energy, and very few quanta. Somewhere in the middle you would expect a peak where the total energy is not too large and the number of quanta is greatest -> this is the peak in the graph that the physicists were trying to explain..
If you want more information I suggest you visit these cool sites:
http://hyperphysics.phy-astr.gsu.edu/hbase/mod6.html#c2
http://www.steelypips.org/principle...iplearchive.php
The second one is extremely good for understanding. Good luck, and mind you the dotpoint only says "identify" so don't get too concerned with it
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From a post I wrote a while back..
