Question

A coil of 1,000 turns encloses an area of 85 cm^2. It is rotated in 0.090 s from a position where its plane is perpendicular to Earth's magnetic field to one where its plane is parallel to the field. If the strength of the field is 6.0 x 10^-5 T, what is the average emf induced in the coil (in mV)?

Answer 1

The average emf induced in the coil is
`5.6*10^(-3)\ mV`.

Step-by-step explanation:

Given that,

Number of turns = 1000 turns

Area = 85 cm²

Time = 0.090 s

Its plane is perpendicular to Earth's magnetic field.

Angle = 0°

Magnetic strength
`B=6.0*10^(-5)\ T`

We need to calculate the magnetic flux

Using formula of magnetic flux

`\phi=BA\cos\theta`

Put the value into the formula

`\phi=6.0*10^(-5)*85*10^(-4)*\cos0^(\circ)`

`\phi =6.0*10^(-5)*85*10^(-4)*1`

`\phi=5.1*10^(-7)\ Wb`

We need to calculate the average emf induced in the coil

`\epsilon=(d\phi)/(dt)`

Put the value into the formula

`\epsilon=(5.1*10^(-7))/(0.090)`

`\epsilon=0.0000056\ N`

`\epsilon =5.6*10^(-3)\ mV`

Hence, The average emf induced in the coil is
`5.6*10^(-3)\ mV`.