A transverse plane wave is incident normally in vacuum on a perfectly absorbing flat screen.
(a) From the law of conservation of linear momentum, show that the pressure (called radiation pressure) exerted on the screen is equal to the field energy per unit volume in the wave.
(b) In the neighborhood of the earth the flux of electromagnetic energy from the sun is approximately 1.4 kW/m2. If an interplanetary "sailplane" had a sail of mass 1 g/m2 of area and negligible other weight, what would be its maximum acceleration in meters per second squared due to the solar radiation pressure? How does this compare with the acceleration due to the solar "wind" (corpuscular radiation)?