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Homework Help: Generator connected to transformer- Find angular speed of coil

  1. Apr 3, 2010 #1
    1. The problem statement, all variables and given/known data

    A generator consists of a circular coil of radius 0.2 meters wrapped 10 times and is spun in a uniform magnetic field of 0.38 Tesla. It is connected (on the primary side) to a transformer with 7 turns on the primary side and 20 turns on the secondary side. If the secondary side is connected to a resistance of 8 ohms and a maximum current of 63 amps is required on the secondary side, at what angular speed should the coil be spun in the generator in rad/s?
    2. Relevant equations

    Vs =Ns/Np (Vp) or ξs =Ns/Np(ξp)
    ξ= N B A w sin (wt), ξmax= N B A w

    3. The attempt at a solution

    What's the first step to solve this problem? Do I try to solve for the ξprimary which would also be equal to ξmax, since the maximum current is applied? Do I then use ξmax= N B A w to solve for w?
  2. jcsd
  3. Apr 4, 2010 #2


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    Homework Helper

    You know the maximum output voltage as the loading resistance and the maximum current is given. From here, you can calculate the required angular speed of the generator by using the equations you cited.

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