Light with an energy flux of falls on a non-reflecting surface at normal incidence

PHYSICS · Subjective · CBSE · Physics · Electromagnetic Waves · Electromagnetic Waves

Problem

Light with an energy flux of

18\,\mathrm{W\,cm^{-2}}

falls on a non-reflecting surface at normal incidence. If the surface has an area of

20\,\mathrm{cm^2}

, find the average force exerted on the surface during a

30\,\mathrm{min}

time span.