The current in a coil with a self-inductance of 1.5 mH increases from 0 to 1.0 A in a tenth of a second.What is the induced emf in the coil?
A)15 mV
B)30 mV
C)0.10 V
D)0.30 V

Question

Quizplus · Accepted Answer

The induced emf (ε) in a coil is given by the formula ε = -L * (ΔI/Δt), where L is the self-inductance, ΔI is the change in current, and Δt is the change in time. Here, L = 1.5 mH = 1.5 x 10^-3 H, ΔI = 1.0 A, and Δt = 0.1 s. Substituting these values, ε = -1.5 x 10^-3 * (1.0/0.1) = -15 x 10^-3 V = -15 mV. The negative sign indicates the direction of the induced emf opposes the change in current, but the magnitude is 15 mV.

The Current in a Coil with a Self-Inductance of 1