Photon fundamentals.
(a) Show that hc = 1240 eY·nm.
(b) Calculate the energy of a photon with each of the following wavelengths: 650 nm (red light); 450 nm (blue light); 0.1 nm (x-ray); 1 mm (typical for the cosmic background radiation).
(c) Calculate the number of photons emitted in one second by a 1-milliwatt red He-Ne laser λ= 633nm.