Honestly all you need to do in prelim physics to just pay attention to fundamental the concepts in class, and really know how to apply formula in whatever situation your been given.
That simple I hardly payed any attention in class, nor did I study only before half and yearly exams, my results were around the 30 to 40% and rank 48th out of 56 for prelim and I was told by the head teacher to drop or else my HSC results will look more like 10 to 20%, but I put my head down at the start of long holidays and I’m currently rank 8th with average of 70 to 80%
So don't stress too much in prelim, just save a lot of your motivation deep inside be you going to need it for HSC