Questions About Stefan-Boltzmann Law

[mp44]

Hi, I have a few questions about Stefan-Boltzmann's law. Let's say that the temerature of an object increases for 2 degrees Celsius, that means that the emmited energy of a surface of that object will increase 16 times. Is this happening because the number of photons is increased 16 times or is the energy of 1 photon increased 16 times or something in between? What is the correlation between temperature of an object and the number of photons it emmits (if one exists)? Let's say in the example of light bulb, if the temerature of a light bulb increases will the light bulb glow brighter, and if it does is it because of an increase of a number of photons or the increase of the energy of 1 photon?

 

[DrClaude]

Something in between.

Check out Planck's[/PLAIN] law for the details.

 

[DrClaude]

Let's say that the temerature of an object increases for 2 degrees Celsius, that means that the emmited energy of a surface of that object will increase 16 times.

I forgot to say: are you sure about that number?

 

[mp44]

I forgot to say: are you sure about that number?

Pretty sure,the energy increases with temperature on the 4th,about Planck's law-my english is not that good

 

[DrClaude]

Pretty sure,the energy increases with temperature on the 4th

But power ∝ T⁴ doesn't mean that if you increase by 2 K, power increases by a factor of 16. That is true if you double the temperature.

about Planck's law-my english is not that good

The link I gave is to Wikipedia, where you may find a version in your language. And it's about the formulas, not the text. Just look at the figure at the top, which shows spectral radiance as a function of wavelength for different temperatures.

 

[mp44]

But power ∝ T⁴ doesn't mean that if you increase by 2 K, power increases by a factor of 16. That is true if you double the temperature.
Sorry,that is what I ment,my mistake.

The link I gave is to Wikipedia, where you may find a version in your language. And it's about the formulas, not the text. Just look at the figure at the top, which shows spectral radiance as a function of wavelength for different temperatures.

Sorry,that is what I ment,my mistake.
Version in my language isn't very helpful since it has only few lines,formulas don't help at all but the picture does.Let's if I got it right-spectral radiance is the density of the radiation,right? So for 5000 K spectral radiance (density) is about 12,5 for the 0,6 picometers wavelength and for 4000 K density is 4 but also there is a decrease in energy because the most freqent wavelength at that temperature is 1 picometers which has less energy than photon at 0,6.