The magnetic flux in the loop changed from 24 to 72 Wb in 4 seconds.

The magnetic flux in the loop changed from 24 to 72 Wb in 4 seconds. The loop resistance is 12 ohms. Find the magnitude of the induction current.

Solution.
The electromotive force created by the alternating magnetic flux is determined by the ratio ε = ΔФ: t, where ΔФ = Ф₂ – Ф₁ is the change in the magnetic flux over time t. On the other hand, the electromotive force is determined through the magnitude of the induction current I and the resistance of the circuit R according to the formula ε = I: R. Combining the formulas, we obtain: (Ф₂ – Ф₁): t = I: R. From the condition of the problem it is known that the magnetic flux in the circuit changed from Ф₁ = 24 Vb to Ф₂ = 72 Vb in time t = 4 seconds. The loop resistance is R = 12 ohms. Substitute the values ​​of physical quantities into the formula and make calculations to find the value of the induction current:
(72 – 24): 4 = I: 12;
I = 144 (A)
Answer: the magnitude of the induction current is 144 amperes.