"Physics was my worst subject in school."

Translation: Fysik var mitt sämsta ämne i skolan.

[jayagmon]

why is värsta wrong?

[nphx2]

Värsta is slang for amazing/best if I am not mistaken.

[devalanteriel]

Yes, but it also means just plain "worst". In this case, using sämsta has the meaning of "the subject I did the worst in", but värsta can sound like "the subject I hated the most" since it's stronger and often has less to do with the quality. Hence I would avoid it here. But they are very often synonymous, and it's mostly just a matter of nuance.

[pikkupapu]

Because it's eeevil ;) But seriously, thelocal.se explains it as a difference of being bad from within and just temporary badness. "Hostan är värre och patienten mår sämre." The illness is bad throughout, but the patient isn't.

[PJamesM]

Interesting, though I'm not really sure I have an intuitive understanding of the distinction. Is it the difference between being inherently bad and being in a bad condition? I'm still not sure how I'd decide which a hated school subject would be.

[david967443]

When should we use fysik for "physics," and when fysiken?