I would like to know the difference between these two terms, and whether they are interchangeable or not. Here are two examples that have the same meaning for me:
"Someone has ripped out the first three pages of this book." "I will rip your head off!"
"Rip" implies to say that someone is going to tear something off. Since both sentences are talking about something being tore off, for instance: Someone ripped my head off, but not only ripped it and made a wound, but also cut it off my neck, it means my neck no longer has a head, it was cut off. So, "out" and "off" implies to say the same thing, why then are there two forms? Do they have different meanings? For instance "rip off" means ripping something off savagely, while "rip out" means ripping something off not so savagely? Or "rip off" doesn't mean "cut my head off my neck" but means only make a wound, while "rip out" means to cut my head off?
Could anyone explain me the difference between them and tell me whether they are interchangeable or not?