The magnetic flux in 0.01 s changed from 9.6 wb to 2 wb. Determine the emf induction in a wire in this field.

To solve this problem, we will use Faraday’s law, which can be written as follows:

εi = – ΔФ / Δt,

where εi is the induction EMF, ΔФ is the change in magnetic flux, Δt is the time of change in the magnetic flux, the minus sign shows that εi and ΔФ / Δt – always have opposite signs.

It should be noted that:

ΔФ = Ф2 – Ф1.

Taking into account the last formula, we get:

εi = – (Ф2 – Ф1) / Δt.

Let’s calculate the EMF of induction:

εi = – (Ф2 – Ф1) / Δt = – (2 – 9.6) / 0.01 = 7.6 / 0.01 = 760 (V).

Answer: εi = 760 (B).