A 6.7 cm diameter circular loop of wire is in a 1.27 T magnetic field. The loop is removed from the field in 0.16 ss . Assume that the loop is perpendicular to the magnetic field.

Required:
What is the average induced emf?

Respuesta :

Answer:

The induced emf is [tex]\epsilon = 0.0280 \ V[/tex]

Explanation:

From the question we are told

    The diameter of the loop is  [tex]d = 6.7 cm = 0.067 \ m[/tex]

    The magnetic field is  [tex]B = 1.27 \ T[/tex]

    The time taken is  [tex]dt = 0.16 \ s[/tex]

Generally the induced emf is mathematically represented as

          [tex]\epsilon = - N * \frac{\Delta \phi}{dt}[/tex]

Where  N =  1 given that it is only a circular loop

            [tex]\Delta \phi = \Delta B * A[/tex]

Where  [tex]\Delta B = B_f - B_i[/tex]

   where [tex]B_i[/tex] is  1.27 T  given that the loop of wire was initially in the magnetic field

    and  [tex]B_f[/tex] is  0 T given that the loop was removed from the magnetic field

Now the area of the of the loop is evaluated as

          [tex]A = \pi r^2[/tex]

Where r is the radius which is mathematically represented as

       [tex]r = \frac{d}{2}[/tex]

substituting values

       [tex]r = \frac{0.067}{2}[/tex]

        [tex]r = 0.0335 \ m[/tex]

So

         [tex]A = 3.142 * (0.0335)^2[/tex]

          [tex]A = 0.00353 \ m^2[/tex]

So

      [tex]\Delta \phi = (0- 127)* (0.00353)[/tex]

      [tex]\Delta \phi = -0.00448 Weber[/tex]

=>    [tex]\epsilon = - 1 * \frac{-0.00448}{0.16}[/tex]

=>   [tex]\epsilon = 0.0280 \ V[/tex]