Frank Szmulowicz, Ph. D. May 7, 2019:

Good point, M. A. B.

M.A.B. May 7, 2019:

I guess vibrations is more an engineering term while oscillations occur rather in physical sciences. Perhaps similar like with speed vs. velocity which in everyday language are the same.
Anyway I'd translate drgania = oscillations; wibracje = vibrations.

Frank Szmulowicz, Ph. D. May 7, 2019:

Historically, different phenomena are referred to either as oscillations or vibrations and, often, both. A guitar string vibrates, the electric field oscillates as does a swing, atoms vibrate, for example.

Frank Szmulowicz, Ph. D. May 7, 2019:

Prawda.
Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point.
https://en.wikipedia.org/wiki/Vibration

M.A.B. May 7, 2019:

To nie jest (całka oznaczona kwadratu) amplitud itd. tylko (całka oznaczona) kwadratu amplitud itd.
Kwadrat odnosi się do amplitud, a nie do całki.