In inductors (letter L) Eli signifies EMF voltage (letter E) leading the current (letter I) by 90 degrees.
In capacitors (letter C) Ice signifies current (letter I) leading the EMF voltage (letter E) by 90 degrees.
Although resistors are not part of this memorization phrase, the current and voltage are always in phase through a resistor.
Why does the voltage lead the current in an inductor?
An inductor is made up of a magnetic material that creates a magnetic field circling the wire when current flows through it. Energy is stored in the magnetic field and in general an inductor resists changes in electric current. Thus, the voltage accumulates in the inductor, and when it reaches a maximum and begins the decrease, the current begins to flow (it was at 0 up until this point). Once the voltage goes to 0, the current reaches a maximum. Once the voltage goes to a negative maximum, the current goes to 0. The cycle continues...
Behavior of a resistor (graph A) and an inductor (graph B)
Why does the current lead the voltage in a capacitor?
Capacitors are like batteries, current flows onto the plates and gives it "charge" or voltage. At one point, the capacitor will reach the maximum amount of charge necessary, and thus that's when it won't accept anymore current (current = 0 at that point) and it will begin to discharge (voltage begins to go down once it has reached its peak).
Behavior of a capacitor:
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