Question

You are looking down on a N = 9 turn coil in a magnetic field B = 0.5 T which points directly down into the screen. If the diameter of the coil d = 3 cm, and the field goes to zero in t = 0.14 seconds, what would be the magnitude of the voltage (in Volts) and direction of the induced current? Indicate the direction of the current by the sign in front of your voltage: counterclockwise is positive, clockwise is negative.

Answer 1

The magnitude of the voltage is
`2.27*10^(-4)\ V` and the direction of the current is clockwise.

Step-by-step explanation:

Given that,

Number of turns = 9

Magnetic field = 0.5 T

Diameter = 3 cm

Time t = 0.14 s

We need to calculate the flux

Using formula of flux

`\phi=NAB`

Put the value into the formula

`\phi=9*\pi*(1.5*10^(-2))^2*0.5`

`\phi=0.003180`

We need to calculate the emf

Using formula of emf

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

`\epsilon=-(0.003180)/(0.14)`

`\epsilon =-0.000227\ V`

`\epsilon=-2.27*10^(-4)\ V`

Negative sign shows the direction of current.

Hence, The magnitude of the voltage is
`2.27*10^(-4)\ V` and the direction of the current is clockwise.