If a player exiles a spell that is represented by a physical card (i.e. not a copied spell), does the physical card go into the exile zone?
Example spell that exiles: Mindbreak Trap
Exiling a spell is the same as exiling any other object: that object is "move[d] ... to the exile zone from wherever it is" (C.R. 701.11a). Indeed, an object can be moved this way even if it isn't a card (C.R. 109.1) (but tokens, copies of spells, and copies of cards will cease to exist as a state-based action if they're in exile [C.R. 704.5d-e]).
Example spell that exiles: Mindbreak Trap