Science Buddies: "Ask an Expert"

Posted: **Sun Jan 23, 2022 2:45 pm**

Hi,

I am doing the "Particles in the Mist" project and I was wondering why I need to cut my PB-210 needle before putting it in the cloud chamber. It fits in the petri dish even if I don't cut it, so I was wondering if there is another reason.

Thank you!

[Administator note: project: https://www.sciencebuddies.org/science- ... #procedure]

Posted: **Tue Jan 25, 2022 10:08 am**

Does it fit in the dish with the cork?

The note says you simply need to cut it so that the needle (+ cork) fit in the dish.

If you are using a 210Pb needle source, prepare it for testing. You will be cutting the needle so that the total length of the needle (cork included) is less than the diameter of the petri dish, as you will put the source in the dish. If you are using a smoke detector as your radioactive source, skip this section and proceed to the next.

Amy
Science Buddies

Science Buddies: "Ask an Expert"

Question about cutting a source needle

Question about cutting a source needle

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