Hollow coil That is, when the current in the coil changes, the hollow coil will attack the induced electromotive force, and the induced electromotive force will resist the passage of current. It's more abstract, so let's take an example.

Inductance is like a spring when we want to tighten the spring, the spring will give us a rebound force, hollow coil that is, hollow coil spring elasticity is preventing us to tighten the spring. The induced electromotive force is like the spring's rebound force, when the current in the coil attempts to change, the induced electromotive force will suppress it, so that the current can adhere to a relatively balanced situation as much as possible.

Then suppose that after the spring is tightened, we release the hand, the spring will return to its original shape. Hollow coil Is the inductor the same? The answer is yes.

Inductance current energy storage curve can store energy is also a major feature of inductance, hollow coil when the inductor current is too high, inductance in order to adhere to the balance of the current, naturally will store a part of the energy, when the current returns to the initial situation, the inductor will release a part of the energy. Just as the spring stores a portion of the potential energy, the spring does not return to its initial shape at once, it will vibrate repeatedly until it has fully released the potential energy.

Another characteristic of inductance is mutual inductance, the current of one loop attacks a magnetic field, the hollow coil and the magnetic field will affect the second loop, this interaction, we call mutual inductance. The most typical use of mutual inductance is the transformer, which is often seen in our days.