Figure 33-15a, drawn in perspective, shows a system of three polarizing sheets in the path of...

Figure 33-15a, drawn in perspective, shows a system of three polarizing sheets in the path of initially unpolarized light. The polarizing direction of the first sheet is parallel to the y axis, that of the second sheet is at an angle of 60° counterclockwise from the y axis, and that of the third sheet is parallel to the x axis. What fraction of the initial intensity I₀ of the light emerges from the three-sheet system, and in which direction is that emerging light polarized?

Fig. 33-15 (a) Initially unpolarized light of intensity I₀ is sent into a system of three polarizing sheets. The intensities I₁ I₂, and I₃ of the light transmitted by the sheets are labelled. Shown also are the polarizations, from head-on views, of (b) the initial light and the light transmitted by (c) the first sheet, (d) the second sheet, and (e) the third sheet.