time spent in a lab you enjoy for a long period is better than multiple or going for a box check. if you enjoy physics, do physics. if you want to do research on the specific dyes and techniques used by an obscure renaissance artist, do that.
#research
summer epoch
in general bouncing around for more experience isn’t looked upon as favorably. if you have valid reasons to bounce around that should be fine though (ie i had to leave one of my labs because severe stomach flu prevebted me from attending lab meetings for two weeks and for some reason that PI treated the lab as a class with attendance)