An F-Bomb is when the word "Fuck" is dropped by mistake or used in an inappropriate place. Otherwise it's just the word "Fuck". Casual or general use of the of word "Fuck" an is not an "F Bomb".
A movie that uses the word "fuck" repeatedly is not "dropping f-bombs".
David - "...and now Bob with the weather."
Bob - "The weather today is going to be... fuck, who's running the teleprompter? Are we live?"
David - "We'll get back to the weather shortly and we apologize for the f-bomb Bob just dropped."