How Rutherford Discovered Radioactive Decay

Ernest Rutherford was a research student under J.J. Thomson when a discovery would change his life forever: Radioactivity by Becquerel. From that point on, Rutherford would devote his life to the atom and radioactivity, and this video summarizes the first few experiments he did in this field that contributed heavily to nuclear physics and won him the Nobel Prize in Chemistry in 1908.

[RationalThinker]

Hello guys! I made a mistake in this video!

The mistake was in saying that one would expect a linear decay if only measuring alpha or beta particles passing through the metal plates, when in fact it would still be exponential!

If a sheet of metal blocks, say, 20% of all particles that reach it, then the probability that a particle would make it through 1 sheet is 80%, 2 sheets is 64%, 3 sheets is 51.2%, 4 sheets is 40.1%... this is exponential decay!

The reason Rutherford kept experimenting isn't because he expected linear decay, but rather because he noticed a much larger decrease than expected when he added the 12th sheet! This was when the cumulative thickness of the metal was enough to start blocking beta particles as well as alpha particles. Hope this clears things up!

[HotelPapa]

Small nitpick: The electrometer does not measure current. It's an indication of Charge / Voltage

[ernestsmith]

Rutherford took that can of worms (three different types of decay radiation) and made sense of it. Quite an accomplishment!

[Neptunium]

nice video! I only whish it was longer !

[glennwoods]

Great to hear so much in depth information about Sir Ernest Rutherford....
He was first to split the atom, is what I thought he was best known for but you have shown he did so much more than that.
The record for Radio wave transmission for example...

[BhavyangBhatt]

It's 1:25 AM, tomorrow I have a physics exam....but as soon as I saw that you posted a new video; I had to watch it....❤👍

[Curiosity-NZ]

Ernest Rutherford was born in New Zealand at Brightwater, Nelson. His birthplace still stands at Brightwater. Studied at Canterbury Colledge which became Canterbury University and now the Arts Centre in Christchurch, New Zealand.

[MichaelWillems]

Very interesting.
One small note: I’m pretty sure he would have pronounced his surname the usual English way, with a soft “th” sound, as in “the”; rather than the way you pronounced it, with a hard th as in “thick”.

[bxoit]

I looked up "Thoron" and it is one of the isotopes of Radon.

[jimparsons]

That foil experiment was possibly the most important experiment in Chemistry or Physics as it hinted at just how the atom was constructed. If you think about it, the first couple of layers of Al, allowed at least a little of the Helium nuclei to pass, as it turned out. Helium nuclei, positively charged ions, zinging around like in a cloud chamber. Are there other ways ions can be formed? Like high voltage electricity? How high voltage do they have to be? Voltage multipliers or maybe a van de Graaf machine? Boggle. Thanks for the clip.

[stewartmcmanus]

Visited his lab in Canterbury College in Christchurch, New Zealand a few years ago.

[DavidRose-ms]

Rutherford, and Pickering who lead Pasadena's jet propulsion laboratory for the American development of space flight both attended the same small school in the tiny settlement of Havelock. Also Bob Hurst a bomb disposal expert, and Chemist also from the top of the south island oversaw as director at Dounreay for the atomic energy commission industrial research station the development of British fast reactor technology which if developed thoroughly would have been able to make use of plutonium safely for energy. Time and place

[arkexplorer]

Ok this is weird, keep going, compounding any material inside should lead to non-linear, actually I'll be impressed if you could get it linear

[williamogilvie]

I was told, about 60 years ago, that the lab at McGill where Rutherford did his research has been sealed due to the residual radiation. I don't know if that is true or if the building where he worked is still standing. A family friend was a physics professor at McGill. He gave a talk describing the different kinds of subatomic particles and their properties at my high school.

[kevinansley]

Suprised the Aussies havent claimed him yet.

[domenicobarillari]

I find this presentation seems to have a fundamental defect, though given that the author seems to have read the original material it may be a simple misunderstanding or oversimplification: why WOULD you expect to see a linear drop off of some intensity effect with thickness? The automatically applicable attenuation law would be something like the Beer-Lambert law, which IS exponential (after all, the solution of a simple 1st order differential equation of absoprtion). This is what one notes with gammas - was it something special about the highly ionizing alpha or betas that would lead one to expect a linear law instead??

best regards,
DKB

[arkexplorer]

Yòu know like a bullet double the size wont go through a sheet of metal double the thickness

[rogerc]

Electro-radium emits protons, ultrasound blasters

[TheKyprosGaming]

I dont quite understand the linear decay. I get the fact that the superposition of 3 linear decays (alpha, beta, gamma), leads to an exponential decay, but I dont understand, why say beta decay in isolation would be linear. Surely when beta radiation passes through a medium its intensity decreases exponentially? Or am I just missing something?

[arkexplorer]

1/r2d2, if u a spot on the wall, r3d3 doom 😊