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    So, here's the question:

    The K+ may decay via the process:

    K(+) -> muon(+) + muon-neutrino

    Change each particle in this equation to its corresponding antiparticle in order to complete an allowed decay process for the negative kaon, K-.

    K(-) -> ? + ?


    I thought it would be an muon(-) and an anti-muon neutrino, but it was just a muon-neutrino. Why?

    Edit: Just to be a bit clearer, but I seem to work it out that the mark-scheme answer doesn't conserve lepton number, which is why I'm asking.
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    I have completed a similar question in the nelson thornes aqa as pysics book. And this question was in the end of chapter 2 questions.

    the answer to the question is in fact

    K--> u- + (anti)Vu

    So you were correct i suggest if this is the same question that you re read the mark-scheme
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    It's possible it's an error in the mark scheme. It's from a program my school offers called Exam-Pro, which lists 1000's of exam questions. Very useful.

    I'll ask a teacher asap. Thanks.

    Also, it does say it's just a neutrino, not anti. I checked a 100 times. :P
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    Maybe a mistake then, about the lepton number not being conserved in the interaction im not too sure.

    Ill post a screenshot of the markscheme that i was reading off

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    Yes, this is what I did, but the mark scheme said the neutrino remains the same.

    It's Madness I tell you. MADNESS!
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    Ooo, I've just checked B) i) and B) ii) on your screen shot, and they're the same answers to my questions here. So it IS an error in my mark scheme... Or an insane coincidence!
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    (Original post by Doctor Chip)
    Ooo, I've just checked B) i) and B) ii) on your screen shot, and they're the same answers to my questions here. So it IS an error in my mark scheme... Or an insane coincidence!
    It must be a mistake, im just still really confused about the decay, a kaon has 0 lepton number and decays into particles that have both -1 lepton number. Maybe im wrong i dunno, its weird.

    Edit: A u- is considerd a muon and not an anti muon which would be means its lepton number is +1 which would make the interaction conserve lepton number =0
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    Yeah, Muon - is the same as an electron (in terms of charge, not mass). It's known as the heavy electron.

    So, u- is the particle, similar to how e- is the normal particle
    u+ is the anti, the same as how the e+ is the anti.
    So if we're going off of your mark scheme, lepton number is conserved.

    Hope that makes sense...
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    (Original post by Doctor Chip)
    Yeah, Muon - is the same as an electron (in terms of charge, not mass). It's known as the heavy electron.

    So, u- is the particle, similar to how e- is the normal particle
    u+ is the anti, the same as how the e+ is the anti.
    So if we're going off of your mark scheme, lepton number is conserved.

    Hope that makes sense...
    I got abit confused with all the nonsense in this question, i dunno if you saw my edit, but i came to that conclusion aswell

    Hope your exams go well.
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    (Original post by Andrea03)
    I got abit confused with all the nonsense in this question, i dunno if you saw my edit, but i came to that conclusion aswell

    Hope your exams go well.
    You too. Thanks for the help.
 
 
 
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