Question

2. A loop of wire of area 0.7 m is moving into a 0.9 T magnetic field. If it takes 5

seconds for the loop to move from completely outside the field to completely inside the
field, what emf is produced?

Answer 1

fem = -0.126 V

Step-by-step explanation:

Faraday's law is

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

where the flow is

Ф = B . A = B A cos θ

bold letters indicate vectors.

In this case, the normal to the area is parallel to the magnetic field, so the angle is zero and the cos0 = 1

fem =
`- A \ (dB)/(dt)`

in this case they indicate that to carry the loop from outside to inside the field in Δt = 5 s, so we can change them by variations

fem =
`- A (\Delta B)/(\Delta t)`

let's calculate

fem = - 0.7 (0.9 -0) / 5

fem = -0.126 V