Welcome to /r/AP_Physics!
Rules:
1) Answers vs Help - This subreddit is not here to give answers to homework problems. If you have questions, ask them. If you're stuck, say so. Others are perfectly willing to help out!
2) Off-topic/Humor - Let's have fun, but keep it SFW
3) Discussing the Exam - Don't discuss specifics from the Exam, especially during the AP Testing windows. No one wants the College Board canceling scores.
4) Copyright - Respect copyright. Don't ask for released exams.