Ask a physicist anything. (2)

[Cabal]

LOL!!!

Who put those tags there?

PATRICK MOORE PLAYS THE XYLOPHONE

 

[Wiccan_Child]

PATRICK MOORE PLAYS THE XYLOPHONE

I'm ashamed that I don't know how to put tags on my own thread .

 

[canehdianhotstuff]

LOLs!

Where does all the extra stuff come from in that volcano experiment?

it an exothermic reaction (produces energy)

the equation is as such.

(NH4)2Cr2O7 (s) → Cr2O3 (s) + N2 (g) + 4 H2O (g)

The gases coming off are nitrogen and water vapour. The new solid formed is chromium (VI) oxide which is the new "puffing" stuff you see.
However this form of chromium is a hexavalent one meaning it's a very toxic carcinogen.

 

[Cabal]

Below a certain really hot temperature, light and matter separate, if the temperature reaches that again, do light and matter join together?

Uh.....can't say I've heard of that...

Can atoms melt?

Techincally, no.

They can ionise though, which means that electrons get kicked off their parent nuclei. Quite hard to break the nuclei up though, although quite explosive when you do manage it!

That light that can detect blood by making it glow, how does it make it glow?

Fluorescence. Same reason your white laundry shines whiter than white!

Ever done an experiment that went wrong?

Oh, here we go.

I've overfilled a burette and gotten hydrochloric acid all down my arm (not very strong, thank the Lord).
I've gassed myself in the face with sulphur dioxide and another time with deuterated ammonia (radioactive and burning, yummeh)
I've gone so wrong in calculating the year a supernova exploded in our galaxy (approx nine centuries ago) I had it exploding several galaxies away 12 years from now.*

ETA: Oh, and I worked on the LHC - although technically the detectors never broke


*I was VERY hungover at the time.

 

[canehdianhotstuff]

http://www.youtube.com/watch?v=y479OXBzCBQ&feature=related

http://www.youtube.com/watch?v=l9z5-mJ8NZk&feature=related

http://www.youtube.com/watch?v=yN9pioJWTk0

Three fun ones Ive done. Last one is toxic though.

 

[Cabal]

I'm ashamed that I don't know how to put tags on my own thread .

It's that bit on the tags bar that says "Edit tags."

 

[canehdianhotstuff]

Uh.....can't say I've heard of that...



Techincally, no.

They can ionise though, which means that electrons get kicked off their parent nuclei. Quite hard to break the nuclei up though, although quite explosive when you do manage it!



Fluorescence. Same reason your white laundry shines whiter than white!



Oh, here we go.

I've overfilled a burette and gotten hydrochloric acid all down my arm (not very strong, thank the Lord).
I've gassed myself in the face with sulphur dioxide and deuterated ammonia (radioactive and burning, yummeh)
I've gone so wrong in calculating the year a supernova exploded in our galaxy (approx nine centuries ago) I had it exploding several galaxies away 12 years from now.

Lol when I worked for a college as a lab tech. I was sent to refill the sodium hydroxide pellets. Of course I wore gloves, but when reaching in the big bag my lab coat sleeves slide up some. I ended up getting some on my arms, like 5 minutes later I had all this little burning red marks. I washed it off fast to say the least.

I once had a reflux of methyl salicylate I was making erupt out the top of the condenser with such force it hit the ceiling. Make the lab smell all nice and minty though!

 

[Wiccan_Child]

http://www.youtube.com/watch?v=y479OXBzCBQ&feature=relatedhttp://www.youtube.com/watch?v=yN9pioJWTk0

*blinks*

Woah.

It's that bit on the tags bar that says "Edit tags."

Ah, so there is!

 

[Chesterton]

Just an hour ago I was going to ask the physicist how to put tags on threads. Drats! Could've finally stumped him!

 

[Wiccan_Child]

Just an hour ago I was going to ask the physicist how to put tags on threads. Drats! Could've finally stumped him!

*cackles maniacally*

Image of the now:

This nuclear reactor is glowing blue because electrons are travelling faster than light. Hot stuff.

 

[Chesterton]

This nuclear reactor is glowing blue because electrons are travelling faster than light. Hot stuff.

I thought nothing could go FTL?

 

[Wiccan_Child]

I thought nothing could go FTL?

Ah, it's one of those funny things. Nothing can go faster than c, which just so happens to be lightspeed. In the reactor, however, photons are extremely slow, so technically electrons are going faster than light (but not faster than c).

God knows why they glow an eerie blue, though.

 

[Chesterton]

Ah, it's one of those funny things. Nothing can go faster than c, which just so happens to be lightspeed. In the reactor, however, photons are extremely slow, so technically electrons are going faster than light (but not faster than c).

Oh, I thought you meant faster than c.

God knows why they glow an eerie blue, though.

Correct.

 

[Cabal]

I thought nothing could go FTL?

Light has an upper speed limit depending on the medium it's in. If electrons goes from one medium to the other and end up being over the speed limit of light in the second medium, it gives off a characteristic burst of radiation; in the case of the nuclear reactor, when the photons hit....the moderator, I'm guessing.... it showers blue light, aka the rather awesome name of Cerenkov radiation.

Essentially, it's like the light equivalent of a sonic boom.

 

[Cabal]

God knows why they glow an eerie blue, though.

I think you'll find CERENKOV knows

*serious face*

 

[canehdianhotstuff]

Radiation tends to give lots of blue glow. Ionization energy does it as well. Not sure if that is the cause of the Cherenkov radiation.

 

[Wiccan_Child]

Correct.

Oh I see what you did there .

Light has an upper speed limit depending on the medium it's in. If electrons goes from one medium to the other and end up being over the speed limit of light in the second medium, it gives off a characteristic burst of radiation; in the case of the nuclear reactor, when the photons hit....the moderator, I'm guessing.... it showers blue light, aka the rather awesome name of Cerenkov radiation.

Essentially, it's like the light equivalent of a sonic boom.

But why does it glow blue?????

I think you'll find CERENKOV knows

*serious face*

Chalnoth would know...

 

[Wiccan_Child]

OK, I've done some digging, and it seems to be where the electron emits radiation in its standard fashion, but it's always keeping up with the emitted photons. So instead of these photons zipping away, they stay more or less close to the electron that created them. Thus, they all build up on each other (instead of being staggered in a line), creating this nice blue effect.

 

[Cabal]

But why does it glow blue?????

ETA: Whuh, ok, probably just found the mathematical explanation of what you just posted...

Ahhh, didn't know that before.

Frank–Tamm formula - Wikipedia, the free encyclopedia

Energy given off per frequency is proportional to frequency itself, so we'll pick up on the shorter wavelengths more. I just figured it was some kind of spectral effect depending on what the medium the electrons were rattling through was, but apparently not.

Chalnoth would know...

Yes, and ever notice you don't see Chalnoth and Cerenkov at the same time.....

 

[catzrfluffy]

The DANGERS of gummy bears . . .

http://www.youtube.com/watch?v=CJ-pSfXcXtw&feature=fvw

(This is the result of a single gummy bear reacting with molten sodium chlorate, contained in a test tube.)

No wait...this one is more amusing:
http://www.youtube.com/watch?v=uj9D3mc7tVg&NR=1
NOOOOOOOOOOOOOOOOOOOOOoooooooooooooooooooooooooooo!