## Black Body

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

akroberts
Posts: 24
Joined: Fri Sep 28, 2018 12:16 am

### Black Body

What exactly is a black body? What are some examples of what a black body looks like?

juliasloan_4g
Posts: 67
Joined: Fri Sep 28, 2018 12:28 am

### Re: Black Body

Professor Lavelle said a black body is a hypothetical material that can absorb all frequencies of light (it's not real).

Catherine Kim 3K
Posts: 31
Joined: Fri Sep 28, 2018 12:26 am

### Re: Black Body

According to the textbook, a black body is an object that absorbs and emits all frequencies of radiation without favor. The object that is heated, or the "hot object," is known as the black body.

Sam Kelly 1K
Posts: 30
Joined: Fri Sep 28, 2018 12:16 am

### Re: Black Body

So does the concept of black bodies explain why objects go from being red hot to being white hot?

Tony Ong 3K
Posts: 63
Joined: Fri Sep 28, 2018 12:23 am

### Re: Black Body

Do we have to understand the concepts of black body for the midterms? I don't remember Professor Lavelle going over this thoroughly or at all during class?

Jeannine 1I
Posts: 73
Joined: Fri Sep 28, 2018 12:27 am

### Re: Black Body

I believe he mentioned in class that we don't need to know about black bodies, so I wouldn't worry too much about studying them. It's also not on the course outline!

Ashley P 4I
Posts: 64
Joined: Wed Nov 15, 2017 3:04 am

### Re: Black Body

The professor said we do not need to know this for this course (14a) but might for later courses.

Layla Manoochehri
Posts: 29
Joined: Fri Sep 28, 2018 12:28 am

### Re: Black Body

so does that mean we don't need to know about the Stefan-Boltzmann law or Wien's law?

jocelyntzeng
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: Black Body

Nope I don't think we need to know those things

Jeremy Feng 1A
Posts: 30
Joined: Fri Sep 28, 2018 12:18 am

### Re: Black Body

The sun is an example of an "almost" black body (since true black bodies do no exist) because it emits almost every wavelength of light.

KaitlynBali_4B
Posts: 51
Joined: Fri Aug 02, 2019 12:16 am

### Re: Black Body

To add on to these comments, I would like to mention that black bodies absorb a wide range of wavelengths (unlike individual atoms) because the atoms and electrons in black bodies act collectively.