Note that he says "I wasn't particularly good at history or physics" (emphasis added), not "I was not any good at physics." As other comments point out, there i

Note that he says "I wasn't particularly good at history or physics" (emphasis added), not "I was not any good at physics." As other comments point out, there is enough to physics besides math that someone (who was good at math) could easily do well in physics without being considered exceptional.