For what period of time in a circuit with an inductance of 20 mH, when the current changes by 0.5 A

For what period of time in a circuit with an inductance of 20 mH, when the current changes by 0.5 A, an EMF of self-induction of 10V occurs?

Task data: L (inductance of a given circuit) = 20 mH (20 * 10-3 H); ΔI (change in current) = 0.5 A; ε (EMF of self-induction arising in a given circuit) = 10 V.

The time interval during which an EMF of 10 V appeared can be expressed from the formula: ε = | L * ΔI / Δt | and Δt = L * ΔI / ε.

Let’s calculate: Δt = 20 * 10-3 * 0.5 / 10 = 0.001 s or 1 ms.

Answer: EMF of self-induction occurred in a given circuit in 1ms.