A very narrow beam of white light is incident at 56.10° onto the top surface of a rectangular block of flint glass 12.7 cm thick. The indices of refraction of the glass for red and violet light are 1.640 and 1.663, respectively. Calculate the dispersion angle (i.e., the difference between the directions of red and violet light within the glass block).
How wide is the beam when it reaches the bottom of the block, as measured along the bottom surface of the block?