Would i be forced to swear on the bible that i would tell the truth in court even if i don't believe in god?:
No, they can't force you to however, it may impair your credibility so you can instead make an affirmation. 

I do not "believe in god" either, I also will not swear an oath to any state or government either. Many legal documents require a notary seal, I refuse their oath so, instead i make only a documented affirmation, it works and is completely legal.(saves on notary fees to boot)