Hi -

Grateful for expert opinion on the question below please ?

Many Thanks

Two overlapping beams of light of different wavelength la = 83011111 and 3.5, = 450 11111 co- propagate through air and strike the same point on a block of unknown material at an incidence angle 1': 45. The beams travel through the block at speed Ta =0.75 c and 1-5, = 0.74 c. What is the angle between the beams travelling through the material? angle between refracted beams =