How do physics and chemistry relate?
Well, they are both science subjects...
And both are needed to understand the world and universe better, along with biology and mathematics. There is a subject which relies heavily on both chemistry and physics, that is physical chemistry.
In chemistry, you might learn about atoms, ions, and nucleus of an atom and such. All of those models were created thanks to great physicists such as Niels Bohr and Erwin Schrodinger.
Those are some examples in which I think that chemistry is related to physics.