First Answer
You are 3rd seat, unfavorable.
The first two players pass; will you open one spade? If, holding these cards, we were in 4th seat after three passes, we would employ the “Rule of 15” (add HCP plus the number of spades; if it’s 15 or more, open). You have 11 HCP plus five spades (a 16 score under the “Rule of 15”), so we would open in fourth seat. On that basis, we would find it easy to open one spade in third seat, and we would make the same decision at any vulnerability..
Bonus from Val: Sometimes I will treat a weak five-card suit as if it were four cards only, so playing Standard or two-over-one, I might open one club on the South cards. I don’t want a spade lead, a spade contract is unlikely to play well in a 5-3 fit unless partner’s spades are very strong, and opening one club will locate a heart fit immediately, if we have one. If (like me) you have an appetite for calls that are reasonable but that won’t be selected by many other players, and if you have a tolerant partner, opening one club instead of one spade might produce a very good result.
Say that you open one spade, LHO passes, and partner bids two clubs (Drury, promising three-plus spades and 10+ support points).
Are you strong enough to insist on game, strong enough to invite game, or not strong enough to invite game?