Yes, the Japanese usually use this onomatopoeia word to express their joy after victory, and there is a special national custom in it. I recommend you to watch the movie starring Tom Cruise, the last samurai, in which the leader of a situational samurai is assassinated. At last, when all the people were finished, a samurai asked, how are you? ! At the same time, other people who are still alive answer "ぉ"! It is a national custom to prove that you are alive and your mission is successful (to protect the leader from assassination). I bet 300 points that you won't come back to choose the answer.