The daily cap of reputation you can earn per day is at 200. Does this mean the exceeding reputation is lost or does it get carried over at the next day?
After you get 200 vote/suggested edit reputation, you're done for the day. Excess reputation that doesn't fall under the exception of a bounty or an accept is lost forever.
That said, if you do get a bounty, or an accept, that does not count against your 200 reputation limit. Therefore, it may be possible to get more than 200 in a day, though excess votes or additional edits don't count.
Your reputation cap is per-site, meaning you can gain 200 from votes/edits here, and an additional 200 on Unix and Linux.
No, the exceeding reputation is lost.
This is done to prevent vote abuse.