## Black body for quiz 2 [ENDORSED]

(Wien's law: $T\lambda _{max}=\frac{1}{5}C_{2}$ )

Derek Waters 1A
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### Black body for quiz 2

So black body and it’s wiens law are not needed for quiz 2 right?

Yifei Wang 3G
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### Re: Black body for quiz 2

Actually test 2 covers Chapter 1 up to the end of section 1.5. Black body and wien's law are in 1.4 so they maybe will appear in test 2

Christy Lee 2H
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### Re: Black body for quiz 2

I am pretty sure Dr. Lavelle said we would not be covering black bodies, so you will not need to know Wien's law or Stephen Boltzmann law.

Rebecca Doan 2L
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### Re: Black body for quiz 2

He did not go over it during lecture very much, so I am sure it is not needed for the test.

Peter Dis1G
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### Re: Black body for quiz 2

But overall,it's still an important concept.I recommend looking at it even if not tested.

Sam Smoot 2L
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### Re: Black body for quiz 2

I am pretty sure we were told we will not be tested on blackbody radiation, but it is an important concept for understanding the chapter overall.

Jasmine Botello 2F
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### Re: Black body for quiz 2

Dr. Lavelle told our lecture that we did not have to worry about black bodies for this upcoming test.

aTirumalai-1I
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### Re: Black body for quiz 2

I know we don't have to know Wien's law for Test 2, but I had a question regarding significant digits for the textbook's example problem 1.3 displaying Wien's law:

"The maximum intensity of solar radiation occurs at 490. nm. What is the temperature of the surface of the Sun?"

The only value given in this problem is 490. with 3 sig figs. Why then is the answer to this problem 5.9 x 10^3 K with only 2 significant figures?

kaitlindaugherty3L
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### Re: Black body for quiz 2

According to what Dr. LaVelle said in class, all we need to know for black body radiation is that atoms and molecules usually only absorb or emit unique frequencies that are allowed by their unique electron structure, but black bodies (hypothetically) absorb or emit all frequencies.

Chem_Mod
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### Re: Black body for quiz 2  [ENDORSED]

kaitlindaugherty3L wrote:According to what Dr. LaVelle said in class, all we need to know for black body radiation is that atoms and molecules usually only absorb or emit unique frequencies that are allowed by their unique electron structure, but black bodies (hypothetically) absorb or emit all frequencies.

Correct and well stated. Introduce yourself at the end of class.

lnlyzelda_3J
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### Re: Black body for quiz 2

Test 2 will only include chapter 1 up until section 1.5 with the exception of calculating black bodies, correct?

3J

Chem_Mod
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### Re: Black body for quiz 2

lnlyzelda_3J wrote:Test 2 will only include chapter 1 up until section 1.5 with the exception of calculating black bodies, correct?

3J

Correct. As I have announced many times in class.