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Homework Help: What is E(t) = wNBAsin(wt)

  1. Feb 12, 2010 #1
    1. The problem statement, all variables and given/known data
    Where can I find the defintion of the varaibles? I know w is the angular velocity, A is the Area, and t is time. but what are NB? is B the feild strength? If that is so, then what is N?


    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Feb 12, 2010 #2

    tiny-tim

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    Hi lampshader! :wink:

    Number of turns? :smile:
     
  4. Feb 12, 2010 #3
    Number of cycles?

    If I were to calculate the angular velocity; w = number of 'turns' / time it makes the 'turns'.

    So the denominator is used again as B in, E(t) = wNBAsin(wt)?

    Thanks! =)
     
  5. Feb 12, 2010 #4
    I thought that, when I open my simulation (homework assignment), their are default values and a peak voltage is displayed. So, when I use the equation: E(t) = wNBAsin(wt); and calculate by subsituting in the default values, I am not getting the displayed peak voltage. Ya know?
     
  6. Feb 12, 2010 #5

    tiny-tim

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    Hi lampshader! :smile:

    (have an omega: ω :wink:)
    ah … now i see …

    no, ω isn't a geometrical angular velocity, it's the frequency, of the variable magnetic field, Bcos(ωt).

    So the magnetic flux is φ = NBAcos(ωt), and the emf is E(t) = dφ/dt = ωNBAsin(ωt). :smile:

    (And N is the number of loops of the wire round the area A)
     
  7. Feb 12, 2010 #6
    Thanks, I appreciate your time.
     
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