"It already collapsed because input voltage is zero. There is nowere to get power to create full halfwave that is missed."

You miss the point and may not understand physics too well. Inductors are inductors because they store energy in a magnetic field. When the input voltage is removed, current keeps flowing because the collapsing field keeps charge moving. That current causes its own EMF - voltage - which drops in an exponential way as the mathematics shows.

Your explanations are jumbled, I figure you are a technician but not an engineer or a physicist.

"It already collapsed because input voltage is zero. There is nowere to get power to create full halfwave that is missed."

You miss the point and may not understand physics too well. Inductors are inductors because they store energy in a magnetic field. When the input voltage is removed, current keeps flowing because the collapsing field keeps charge moving. That current causes its own EMF - voltage - which drops in an exponential way as the mathematics shows.