"Do you have a minute?"
Yes and no. In Polish, as with all Indo-European languages that still have T-V distinction, the "proper" forms of address are slowly dying. While many(majority, possibly) Poles would have no problem using it like that, personally I perceive "mieć minutę" as way too colloquial to address a professor and would rather use something like "Czy mogę panu/pani zająć chwilę?" in this context.
On the other hand, in a situation where the person I would address would be of somehow equal status(say, between work colleagues in an office - assuming you would find one where "per Pan/Pani" forms of address are still used ;) ) I would use "czy pan/pani ma minutę?" without second thought.