What will happen in
BTC bitcoin market when another fork hits bitcoin, results in emerging bitcoin gold as new coin
Will price of bitcoin go down
Will new coin get popularity like bch

We could actually see bitcoin price rise after the fork, just like 1st August. However, the fork is likely to cause a lot less commotion and confusion than the bitcoin cash fork, since it is probably not as well advertised by the founders.
Price will not be overly affected by whatever happens with bitcoin gold since it is really just another altcoin after it forks, but if there is a bull market then it could actually go over the $4500 resistance that we are experiencing right now.