Photons do not only carry energy, but also momentum. The momentum (p) of a single photon is: p : k Where h is h/ (21). This causes light to exert a pressure on any surface where light is absorbed or reflected. This pressure can be estimated using the principle of momentum conservation and the denition of a force: FmamaVap _ _ at _ t (a) Find an expression for the pressure exerted by light of intensityj I, on a perfectly absorbing surface. Does it depend on the angle of incidence? Why or Why not