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    We don't need to know about E=mc2, but it would still get you the answer, I was just pointing out, use it as a last resort, as it would work for the jan 13 question for example


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    What time do the exams start for you lot? It's a pm exam I believe


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    Find physics the hardest out of all of my sciences
    I am very nervous!
    Good luck to you all xo
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    Maybe, 6 marker will be on energy level spectra...
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    (Original post by Tuya)
    What time do the exams start for you lot? It's a pm exam I believe


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    1:00pm
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    (Original post by Tuya)
    What time do the exams start for you lot? It's a pm exam I believe


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    Yes pm. But not sure about what time. maybe its at 1pm.
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    Will you need to do calculations for annihilation? If the particle and anti particle have kinetic energy, will that mean the photon energy is the rest energies + kinetic energies divided by 2?
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    (Original post by Didierr)
    Find physics the hardest out of all of my sciences
    I am very nervous!
    Good luck to you all xo
    Very good luck to you too!!!!
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    Bye all!!! It 11pm and I am going to bed for tomorrow! Have a good night sleep and do not worry at all about the exam if you revised for it.
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    (Original post by GeneralOJB)
    Will you need to do calculations for annihilation? If the particle and anti particle have kinetic energy, will that mean the photon energy is the rest energies + kinetic energies divided by 2?
    Yes, as there is 2 photons created to conserve momentum - going in opposite directions.
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    When is discussion legal? As its not edexcel, I'm guessing straight away


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    (Original post by GeneralOJB)
    Will you need to do calculations for annihilation? If the particle and anti particle have kinetic energy, will that mean the photon energy is the rest energies + kinetic energies divided by 2?
    Yes! you could be asked to calculate annihilation energy. rest energy is 0.510999MeV for a single electron. What do you mean by divided by 2? only add the energies together.
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    (Original post by Tuya)
    When is discussion legal? As its not edexcel, I'm guessing straight away


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    I believe so!
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    Good luck ALLLL!
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    Good luck guys!

    (Original post by Tuya)
    When is discussion legal? As its not edexcel, I'm guessing straight away


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    Yup, straight away.
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    (Original post by StalkeR47)
    Yes! you could be asked to calculate annihilation energy. rest energy is 0.510999MeV for a single electron. What do you mean by divided by 2? only add the energies together.
    Well since two photons are emitted, the energy of one photon would be half.
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    (Original post by StalkeR47)
    Yes! you could be asked to calculate annihilation energy. rest energy is 0.510999MeV for a single electron. What do you mean by divided by 2? only add the energies together.
    So for annihilation, its the rest energy for the particle. So approx 0.5mev.

    But for pair production you double it so approx 1.02mev?

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    (Original post by StalkeR47)
    Yes! you could be asked to calculate annihilation energy. rest energy is 0.510999MeV for a single electron. What do you mean by divided by 2? only add the energies together.
    For the total annihilation energy, just add the two together. He just means if it asks for the energy of each photon you would need to divide by two.
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    Do we need to know definitions?
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    Do you not need to consider the kinetic energy of the particle and anti particle before collision though? For energy conservation.
 
 
 
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