Sunlight is incident on a horizontal glass plate with a refractive index of 1.45. Depending on the angle of incidence of the sunlight the reflected ray will exhibit a degree of polarisation in the horizontal direction. (a) Calculate the angle of incidence which will make the reflected light completely horizontally polarised. (b) The horizontally polarised reflected light has an intensity of lo. If it passes through a linear polariser with its transmission axis at 45 to the horizontal, then what will the intensity of the transmitted light be, in terms of l9? (c) What will the direction of polarisation of the transmitted light be in (b)? Give the direction in terms of an angle relative to the horizontal. (d) The polariser is rotated so that its transmission axis is vertical, 90 from the horizontal. Describe what now happens to the horizontally polarised light that strikes it.