The Discovery of the Atomic Nucleus (3 of 15)

[meehalee21]

Oh god its this guy. I'm gonna be up all night now..

[aussie56]

Definitely using this video for my high school physical science course tomorrow. Thank you Brian Cox and your sexy sexy intelligence!

[stupidityunitenstuff]

we watched this is Physics class!

[scbaker465me]

Add EDUCATION to category so this can be used in schools with filters.

[Sal3600]

Ernest Rutherford was a kiwi!

[mbutlig1]

awesome

[dntforgthis]

Our teacher is indian, and i cant understand a word shes saying !!! ;$

Negatively charged particles, positively charged, we will learn all of that. her way "Negatwly chajd patklz, posetwly chajd, ve vill lean all o dat!"

[RichtoffenRoach]

HOW THE FUCK CAN THEY SEE THE FUCKING ELECTRON? HOW DO THEY MEASURE IT? I MIGHT NEVER KNOW

[NANOFORGE]

@RichtoffenRoach Atoms cannot be seen because they don't relect light (they are too small). They can be measured and detected in many ways, I.e through their radioactivity etc, you should read up on it.

[RichtoffenRoach]

@NANOFORGE So those pictures about atoms that i've seen is a lie? How can they play with them? Nanotechnology! Ca you please enlighten me?

[NANOFORGE]

@RichtoffenRoach I'm no physicist but atoms cannot be seen with visible radiation (light) because they don't reflect it. They can be seen via other wavelengths and frequencies of the electromagnetic spectrum.

[zamilabbas786]

British accent is more sophisticated than american, but american accent is cooler.

[trnstlntcsnnt301]

Much better than reading my dirty handwritten notes. Learned more here than from my professor... god, that class was so boring...

[zamilabbas786]

@trnstlntcsnnt301 i feel for you dude

[trnstlntcsnnt301]

Awesome.

[toniroxxxxx]

how many takes did they need before Brian caught the tennis ball!?!? :D

[tenseman08]

THE ELECTRONS WOULD BE A KILOMETRE AWAY!!!! haaha

[mejico94]

two week school lesson in a couple of minutes

[Marqan]

Let's be honest: Philipp Lenard figured the most if it out more than 10 years earlier.

[chaosarcee]

omg wat if we are living on a giant electron!!!!!!!!!!

[Freshhamc]

WHITE FAGGG!!SSSS 

[jeudysd09r]

my teacher made me watch this and take note. really boring.

[Spartanboy3000]

@jeudysd09r Dude so, my DAD is making me watch this, even though I am in front of the friken T.V. and my ps3 is right there. Even Worse, HE'S watching t.v!

[xpsniperguy123]

Your the best! thanks for the sweet video! :)

[blUdz18]

He appears on the New Zealand $100 note. Rutherford is New Zealand's most famous Scientist!!!

[claire0rockz]

I have to watch this for Chemistry at the moment...

[dianaberry9393]

@claire0rockz me too. I have to write a paper on it. Not fun.....

[physicsno1]

an alpha particle is a combination of two protons and two neutrons that are ejected from the nucleus of a radioactive atom. alpha radiation is the most dangerous to your health if injested because its very ionising(i.e can make healthy cells become cancerous). the good thing is that it's not very penetrative. (can't get through skin and can only travel 5cm through air.)

[Rose4Demetri]

im 12 and i get most of this but I don't know what positively charged protons and electricly nuetrel neutrons are and also what alpha particals actually are. Someone told be alpha particals were fem meted atoms?????? but that was a friend who is also 12 so I so I don't really think she is correct, would someone mind explaining. thanx

[TheVladimirtk]

This is so intresting to bad it´s not much more time explaining how thing work=( but they do what they wanna do =) gr8 vids=) ima watch em all

[ollieoniel]

1 in eight thousandth isnt that within reasonable error? and what about background radiation? this i think is the stupidest experiment in history

[ericscerri]

Rutherford derided chemistry and yet was awarded the Nobel prize for chemistry!

see the great book,

Eric Scerri, The Periodic Table, Its Story and Its Significance, Oxford University Press, 2007

[Gman74]

that bit with the geiger-counter is insane!!!!!!

[DeViLiN888]

Such an amazing scientist Sir Ernest Rutherford was. This one person made so many discoveries!!!

[Pirwzwhomper]

my cat just ripped a wicked fart in my lap. she continues purring like it never happened.

[okeeft01]

Thanks but what you're saying is akin to how I learned basic chemistry a decade or so ago at secondary schoo, before quarks, gluons, tauons, neutrinos, mauons came into the basic education picture. I think it's agreed what you say - there is significant distance between the nucleus and orbitting elctrons but what is that "distance" composed of and if the answer is "nothing" could that be the result of matter and antimatter combining?

[mikebe41]

I have thought of the same thing, is the space between the electron and the nucleus, the same kind of space that is outside of the electron. i get where you are going with this. It is very interesting. Of course, the know it alls, say it is the same, but they really dont know

[psychodave0]

as above, it is nothing to do with antimatter. If antimatter and matter were annihilating (NOT COMBINING), a huge amount of energy would be released.

the distance between is comprised of empty space. That is, a vacuum. There are no detectable particles. It is as simple as that.

(of course, this is not the full picture due to electrons having wave-particle duality, but this is a detail best left to actual physicists)

[okeeft01]

So the atom which the presenter previously described as an amorphous blob (like a muffin) actually is mostly made up of "nothing" - is that possible? Or are we going to find particles or matter between the nucleus and the boundary of the atom? Is the "nothing" the result of matter and antimatter combining and the tiny (relative to the size of the atom) particles left over are matter?

[okeeft01]

Alpha particles? The same as the decay of radioactive elements? Or the nuclei of helium? If the atom was an amorphous blob (like a muffin) then I would expect 100% of the alpha particles to be blocked/deflected, not pass through. This video is better than nothing but certainly leaps explanations of phrases and processes.

[CamiloSanchez1979]

I can't believe there are filmed records of Rutherford and Thompson ..That is fucking remarkable.

[almann1979]

the most remarkable fact here is that brian cox really was the keyboard player for D:ream

[mikebe41]

yea and he is younger still than my pool boy...he must be a smartee wiz kid:)

[SoraTakenouchi16]

I feel pretty much lucky to have acces to this information,thanks a lot

[coldheartedsquirrel]

Quantum mecanics does NOT tell that electrons are in destinct shells around the nucleus.

[TheAmericanPageant]

The video never said that quantum mechanics didn't tell that electrons are in distinct shells, but that quantum mechanics does not give exact orbits of electrons.

[Achmed1787]

lol this is actually all i ahevt o see for my physics and chemistry test

[racastilho]

Why did they discard the possibility of the atoms being indeed solid, hard balls, and that the empty space between them was the cause for the alpha particles go through the gold plate?

[wcwashington]

hmmm take two years to brainstorm that question just like they did.

[Gazzar]

If the atoms more closely resembled the solid balls then all of the alpha particles would rebound. If the atoms were comprised mostly of empty space with a solid nucleus in the middle then most of the alpha particles would pass straight through and only a few would, by chance, hit the nucleus and rebound - which is what happened. Hence the nucleus model was accepted in favour of the solid amorphous blob model.

[racastilho]

Good point, but I was thinking of solid balls with gaps between them. The alpha particles to pass through the gaps, not throught the atmos themselves...

Thanks for your reply!

[Orenotter]

If that were the case, racastilho, there would have been a greater, predictable, amount of rebound. Not all, but significantly more than experienced.

[racastilho]

Orenotter, thanks for you comment! It's absolutely amazing how these guys could have a such an insight about the consitution of atoms, without ever observing them directly... Fantastic...

[Orenotter]

I think that speaks a great deal to just how amazing our universe is. So much of it is counter-intuitive, yet if we do the math, it all makes sense. It's just fascinating and totally brilliant.

[billyx333]

didnt read all these comments but my take is that the results wouldve been reversed if that were the case, all of them would rebound and 1/8000 would pass through (wow 9 months late oh well)

[racastilho]

Thanks for your comment billyx333!

[RJL738]

Even with the uncertainty principle, electrons are particle-like in nature and the shells are just very complex 3-dimentional orbits, meening they can't get much closer/further from the nucleus but they can go in any other direction. Also they go at roughly 90% the speed of light. Even though not nearly as much, their is also an amount of space between the protons/nuetrons.

[jespriella]

Is that why we can not pass through walls?

[pirskwayrd]

No, that's because the outter shell of every atom is comprised of electrons which all have a negative charge. Like charges repel.

[rusurazvan]

i still dont get it, he says just a part of atoms get throught but th eother part ot, that means we left a part of us int the wall?

[pirskwayrd]

when you touch the wall you can no longer speak about you or the wall, only the "you-wall" system. the electrons floating around in you and in the wall may freely exchange, this is how you gain/lose charge.

think of why you ground yourself by touching metal before you open up your computer.

[VINHQLUONG]

@pirskwayrd Um...alpha particles have positive charges. Beta has negative charges. XD

[hellobal100]

@pirskwayrd then y electrons in the same shell never repels?

[rsworker]

Thank you for explaining this, makes alot more sence