Recent content by ChumpusRex

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    Radiation emissions from glow-in-the-dark toys

    A while ago I bought some novelty keyrings which contained tritium powered lamps. The marketing information mentioned that the beta particles would be contained by the acrylic shell of the keyring. A not unreasonable claim given the low energy of the tritium beta emission, and lack of...
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    Two Protons Colliding- Stable Nuclei?

    Yes, they can. It takes substantial energy - but it does happen, it's just difficult to achieve on earth. However, the process of proton-proton fusion is one of the key reactions that takes place in the sun. 2 Hydrogen nuclei (protons) fuse to produce a deuterium nucleus (1 proton, 1 neutron)...
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    Physics of coordination and reflexes

    Can you be a little more specific? Do you mean the general mechanics of forces, levers, fulcrums and masses? Do you mean the molecular aspects of muscle contraction? Do you mean the anatomy and function of the muscle control loops for reflexes/posture? Do you mean the inverse kinematics and...
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    X-ray fluorescent screens and film contrast

    It's common practice in radiography, especially medical radiography where radiation doses are relevant, to use a fluorescent screen to expose photographic film, rather than rely on the effect of x-rays on the film itself. I understand the concept of fluorescence and the overall photon...
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    Why is the Anode at the Center of a GM Tube?

    Many thanks. A clear answer. I had suspected it was something to do with the increased field strength at the centre of the tube, but was unsure of the reason.
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    X-Ray lines from inner shell ionisation

    The probability of a particular transition occurring depends on more than the number of electrons in a particular shell. E.g. in the event of a K-shell ionisation, the return to ground state may be by: capture of an L shell electron (59.3 keV) + subsequent M-> L transition (approx 9-10 keV)...
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    X-Ray lines from inner shell ionisation

    There is a possibility that electrons from any shell may be excited or freed from the atom. As the a result the characteristic radiation includes not just transitions from L and M shells to the K shell, but transitions from the M shell into the L shell. The energy differences between the higher...
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    Why is the Anode at the Center of a GM Tube?

    Why is the GM tube polarised? What benefit comes from having the anode at the centre of the tube? What happens if you reverse the polarity?
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