First off, don't feel discouraged about the losses, I haven been 0-4 before as well but managed to be 5-5 by the end of placements.
It actually varies, one time I was 4-6 and got Silver 3, on other acc was also 4-6 but got Bronze 1 (both accounts were were unranked previous season). On this current I went 5-5 and got Silver 3.
Anyway, just do your best and try to end with at least 4 wins, you'll start facing lower ranked players and are more likely to carry. Even if you get placed in Bronze 1-2 it's hella easy to get out if you pick easy-to-play hard carry champs.