By relating temperature to particle motion, the kinetic theory of gases gives an intuitive explanation of conductive heat transfer; faster particles collide with slower ones to transfer kinetic energy. But how does electromagnetic radiation make matter warmer? I would imagine a photon hitting a particle makes it faster, but how does it do that? Moreover, a photon hitting a particle is responsible for the photoelectric effect. Electron emission doesn't sound related to speeding up the whole particle's motion; are they competing phenomena?