Question

A magnetic B field of strength 0.9 T is perpendicular to a loop with an area of 3 m2. If the area of the loop is reduced to zero in 0.5 s, then what is the magnitude of the induced emf voltage?

Answer 1

The magnitude of induced emf is 5.4 V

Step-by-step explanation:

Given:

Magnetic field
`B = 0.9` T

Area of loop
`\Delta A = 3`
`m^(2)`

Time take to reduce loop to zero
`\Delta t = 0.5` sec

To find induced emf we use faraday's law,

Induced emf is given by,

`\epsilon = -(\Delta \phi)/(\Delta t)`

Here minus sign shows lenz law, for finding magnitude of emf we ignore it.

Where
`\phi = B\Delta A`

Put the value of flux and find induced emf,

`\epsilon = (B\Delta A)/(\Delta t)`

`\epsilon = (0.9 * 3)/(0.5)`

`\epsilon = 5.4` V

Therefore, the magnitude of induced emf is 5.4 V