When do the lines of flux cut across the inductor coil?

When do the lines of flux cut across the inductor coil?

• A. To slow down current surges and spikes
• B. To generate constant current
• C. To increase voltage
• D. To decrease resistance

Answer: (A)

Inductors resist changes in current because their magnetic field links with the winding. When the current through the coil changes, the magnetic flux through the coil changes as well, so the lines of flux effectively cut across the turns. This changing flux induces a voltage in the winding that opposes the change in current (Lenz’s law). That opposing voltage slows down rapid changes, so it dampens current surges and spikes. If the current were steady, the flux wouldn’t change and no opposing voltage would be generated. So the lines of flux cut across the coil during changing current, producing the effect of slowing those rapid transitions. The induced voltage is proportional to the rate of change of current (V = L di/dt), which underpins this behavior.

Inductors resist changes in current because their magnetic field links with the winding. When the current through the coil changes, the magnetic flux through the coil changes as well, so the lines of flux effectively cut across the turns. This changing flux induces a voltage in the winding that opposes the change in current (Lenz’s law). That opposing voltage slows down rapid changes, so it dampens current surges and spikes. If the current were steady, the flux wouldn’t change and no opposing voltage would be generated. So the lines of flux cut across the coil during changing current, producing the effect of slowing those rapid transitions. The induced voltage is proportional to the rate of change of current (V = L di/dt), which underpins this behavior.