Two polarizing sheets have their transmission axes crossed sothat no light gets through. A third sheet is inserted between thefirst two so that its transmission axis makes an angle ?with the transmission axis of the first sheet. Unpolarized light ofintensity I0 is incident on the first sheet.Suppose that the middle sheet is replaced by two polarizing sheets.The angles between the transmission axes of the second, third andfourth sheets in the stack make angles of 30
