Question

Consider a 120-W red light bulb, producing unpolarized light uniformly in all directions with a wavelength of 710 nm. (Assume that the bulb is perfectly efficient, converting all the power delivered to it to light.) A photocell with an area of 1×10-4 m2 is placed a distance of 2.00 m from the bulb.

a) (4 pts) What is the frequency of the light reaching the photocell?

b) (10 pts) How much energy is delivered to the photocell in one hour?

c) (6 pts) What is the magnitude of the rms electric field of the light incident upon the photocell?

d) (10 pts) You wish to reduce the intensity of the light reaching the photocell by a factor of three by placing two thin polarizers immediately in front of photocell. What should be the angle between the transmission axes of the polarizers?

Answer 1