How detrimental is a drop in grades?

I’ve kept a 4.0 UW GPA all throughout high school. I applied RD to Harvard and know that I’ll need to submit a mid-year report. It’s pretty likely that I’m going to get a B in physics, but keep an A in everything else. My class schedule for both junior and senior year featured spanish, english, calc, physics, psych, and history (all IB). I’m a full IB diploma candidate, and throughout my application I make it clear that math and science aren’t of great interest to me; I’m much more into politics, psychology, philosophy, etc. This also connects to how speech and debate is my main EC. How detrimental will getting a B in physics be in my chances of admission?

Many students have been accepted to HYP with B’s on their transcript. That said, applying to any college RD with a low single-digit acceptance rate is like buying a lottery ticket. Sure, you have a chance to win the jackpot, but realistically no one stands a good chance – not even students with perfect GPA’s and test scores. Did you read the story about the Intel Science Fair Winner who made a fusion reactor in his garage and was rejected by MIT? If kids like that are rejected by the ivies and their peers, who knows what will happen with your application. Do the best you can and don’t sweat it. If you are rejected, it will not be because of a lone B on your transcript.