If my child and I are in a room, and I want him to go out so I can work, I say "Can you go out so I can work?", but he won't go out and I want to urge him to leave the room, and if I just said "Go out!", he wouldn't know what it meant. Because it doesn't have a clear meaning, it could mean going out shopping, going to a bar, going for a walk... So if I add the word "now or on": Go out now! Go on out! Does he understand now that I want him to leave the room? I mean, does it mean the same as "Get out!"? I only care about you leaving the room, not about where you're going.