Cloud Chamber Set up? (1 Viewer)

[Kukudas]

How do u set up cloud chamber??

 

[Kukudas]

thx

so for cloud chamber
u only have to know
set-up and results (observtation)??
wat else do you to know;;

 

[willC]

Aim too of course, and interpretation of results

 

[Kukudas]

result as in
alpha and beta and gamma rays right?

 

[willC]

It also lets us see some of the properties of the different radiation types:

Alpha rays produce thick, short trails-suggesting they are large with little penetrating ability.

Beta produces very thin long trails-small, highly penetrating particles.

As for gamma, you cant really detect it very well in a cloud chamber...

 

[helper]

Remember the need for a risk assessment

 

[jlnWind]

For the less fortunate, like me, we didnt actually get to do the experiment
so i dont think you'd extreme details, especially because the dot point asks

perform a first-hand investigation or
gather secondary information to
observe radiation emitted from a
nucleus using Wilson Cloud Chamber
or similar detection device

So i dont think the set up is essential. But maybe understanding whats actually happening (supersaturated alcohol causes the ionised trail to act as condensation centres --> cloudy trails)

The important bit is being able to explain why the tracks are as observed. This was put quite nicely by willC, may want to mention the fact that they ionise less/ more which means less/ more collisions which means longer/shorter trails.

Like the most likely thing they'd ask you to do is interpret a photo of wilson cloud chamber, and explain what collisions are happening.

 

[samwell]

Ha Ha a cloud chamber isn't..that difficult to set up. Its just the possibility of seeing the cloud trails that was my problem at school.

Apparatus (for my experiment):

One Wilson Cloud Chamber with lamp
Dry Ice
methylated spirits
source of alpha particles eg americium-241? (alpha particles are larger and heaps easier to observe)

Method:

1. Fill the underside of the chamber with dry ice to cool it down
2. Apply methylated spirits on top, i used a tissue and wiped the surface of the cloud chamber so that there would be saturation when I closed the cover
3. Turn on the lamp
4. Place the radioactive source on the side of the chamber (inside)
5. Observe

If you get lucky like I did second time round, you'll see little cloud trails appearing then dissolving away coming from the radioactive source.

But we know there ain't no such thing as luck in science, and found out we put too little dry ice in the first time round

Risk assessment? Don't play around with radioactive materials...

Hope that helps

My class did practically the same thing but we used alcohol instead of spirits <think propanol>and we got results. we could even observe better rays from the cloud chamber using ceasium.
{edit: remember methylated spirts are very volatile and that could have been an issue in ua prac as the incandescent lite gets hot}
Just wondering how did ua Hydrogen spectrum prac go? for neon sodium and nitrogen was beautiful but for hydrogen it wasnt as well defined considering the variables we failed to control well.

 

[darkwolfzx]

rofl at post i made yonks ago

 

[samwell]

rofl at post i made yonks ago

lol 1 year l8er

 

[Js^-1]

Hey I was wondering; We didn't get to do a cloud chamber experiment, instead we played around with a Geiger-Muller Counter and some sources, putting aluminium plates between them, and that sort of thing. For the Hsc, should I learn the theory and pretend I did the cloud chamber experiment, or can I use the one i did in class? The syllabus is a bit ambiguous on this dot point. It says '...using a cloud chamber or similar device...". A Geiger-Muller Counter is a device for detecting radiation, but it doesn't show radiation trails, just the presence of radiation.

 

[samwell]

Hey I was wondering; We didn't get to do a cloud chamber experiment, instead we played around with a Geiger-Muller Counter and some sources, putting aluminium plates between them, and that sort of thing. For the Hsc, should I learn the theory and pretend I did the cloud chamber experiment, or can I use the one i did in class? The syllabus is a bit ambiguous on this dot point. It says '...using a cloud chamber or similar device...". A Geiger-Muller Counter is a device for detecting radiation, but it doesn't show radiation trails, just the presence of radiation.

You can also study the principle of the geiger counter. Its use of an electrode and ionisation of Argon gas. U can also discuss why its a better beta detecter. The working of this prac is more theoretical than experimental. I also do think its a good idea to know the cloud chamber prac althought the geiger muller counter is also a good device to talk about.

 

[Js^-1]

Ok cool thanks for that.