In a turbidity system such as that of Figure, the tanks are 2 m in length. A laser with a 2.2-mrad divergence, 2.1-mW power, and 1-mm exit radius is employed.
If the sample nominally detracts from the beam power by 12% per meter, find the intensity of the beam at the detector. The laser is 1.5 m from the beam splitter. Note that the splitter halves the power and does not affect the divergence.
