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    Last part what equation we using?

    Power = work done/time?

    And what are we trying to find.
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    Also the question after asks me to work out the mass.

    Why is the mr 0.239?
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    well if each decay gives 8.2x10-13 Joules, yes you would need to use P=e/t, and dN/dt = A = LambdaN.
    (
    )The rate of decay x the energy per decay would give you the power. So set up the equation A x 8,2x10-13=2.5,

    Mr is always stated a grams per mol, so 0.239 is the mr of Plutonium in kg
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    Bq is number of decays per second
    W is Joules per second

    each decay releases 8.2E-13 J of energy
    how many decays per second are needed to release 2.5J per second?
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    (Original post by Formless)
    well if each decay gives 8.2x10-13 Joules, yes you would need to use P=e/t, and dN/dt = A = LambdaN.
    (
    )The rate of decay x the energy per decay would give you the power. So set up the equation A x 8,2x10-13=2.5,

    Mr is always stated a grams per mol, so 0.239 is the mr of Plutonium in kg
    Cheers
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    AQA?
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    (Original post by Joinedup)
    Bq is number of decays per second
    W is Joules per second

    each decay releases 8.2E-13 J of energy
    how many decays per second are needed to release 2.5J per second?
    Would this be alright?
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    (Original post by Formless)
    AQA?
    OCR, ****ing hate physics man.
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    (Original post by Super199)
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    Would this be alright?
    it's a 'show that' question... probably a one marker
    I'd probably have said

    Power = energy per decay * number of decays per second
    2.5 = (8.2×10-13) * (3.0×1012) (to 2 s.f.)
 
 
 
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