A 120-turn, 9.604-cm-diameter coil is at rest in a horizontal plane. A uniform magnetic field 12 degrees away from vertical increases from 0.316 T to 5.553 T in 98.254 s. Determine the emf induced in the coil.

Respuesta :

Given:

The number of turns is,

[tex]n=120[/tex]

The diameter of the coil is

[tex]\begin{gathered} d=9.604\text{ cm} \\ =9.604\times10^{-2}\text{ m} \end{gathered}[/tex]

The angle of the magnetic field with the coil is

[tex]\theta=12\degree[/tex]

The change in a magnetic field is from

[tex]0.316\text{ T to 5.553 T}[/tex]

in

[tex]t=98.254\text{ s}[/tex]

To find:

The induced emf

Explanation:

The induced emf in the coil is,

[tex]\xi=-nA\frac{dB}{dt}cos\theta[/tex]

Here, the area of the coil is,

[tex]\begin{gathered} A=\pi\frac{d^2}{4} \\ =\pi\times\frac{(9.604\times10^{-2})^2}{4} \\ =7.244\times10^{-3}\text{ m}^2 \end{gathered}[/tex]

The induced emf is,

[tex]\begin{gathered} \xi=-120\times7.244\times10^{-3}\times\frac{5.553-0.316}{98.254}cos12\degree \\ =-0.045\text{ V} \end{gathered}[/tex]

Hence, the induced emf is 0.045 V.