The plane of a that surface is perpendicular to the propagation direction of an electromagnetic wave of intensity 1. The surface absorbs a fraction w of the incident intensity, where 0 < w < 1, and reflects the rest.
(a) Show that the radiation pressure on the surface equals (2 - w) I/c.
(b) Show that this expression gives the correct results for a surface that is (i) totally absorbing and (ii) totally reflective.
(c) For an incident intensity of 1.40kW/m2, what is the radiation pressure for 90% absorption for 90% reflection?