Question:
Light with an energy flux of 20 W/cm2 falls on a non-reflecting surface at normal incidence. If the surface has an area of 30cm2, the total momentum delivered during 30 minutes is
(a) 36 × 10-5 kg m/s
(b) 36 × 10-4 kg m/s
(c) 108 × 104 kg m/s
(d) 1.08 × 107 kg m/s
Solution:
(b) 36 × 10-4 kg m/s