you either love or hate physics. if you got a good teacher, you'll like it. if you have a crappy one like me, you'll hate it. and trust me.. there arent many good physics teachers out there for some very weird reason.
bio requires a lot of memorising. the pracs that you do can be heaps of fun. more excursions (fieldwork). camps possibly. you can also apply it to everyday life more than physics. like you might stumble across a dying leaf and go.. oh that needs more water where as, if you do physics, you wont say "wow the momentum must have been great when that car crashed into that tree!"
not great arguments but hope it helps!
choose chem btw! its the best!