How to calculate angular momentum per second for a photon?

[Ishida52134]

Homework Statement

Given a photon polarization state lphi> = lx> 3/5 + ly> 4i/5 , a beam of photons transmit N photons per second in such a state. An L-polarized photon has an angular momentum hbar along its direction of motion, and an R-polarized photon has an angular momentum of the same magnitude but opposite to direction of motion. If the beam described by the particular polarization state phi above is totally absorbed by a surface, what angular momentum is added to the surface per second on the average?

Homework Equations

The Attempt at a Solution

So, I know the total angular momentum is Nhbar. I'm not sure if I have to calculate the direction perpendicular to the surface or the full angular momentum which would be Nhbar.

 

[Simon Bridge]

The beam is "totally absorbed" ... how does a beam transfer angular momentum to a surface?