Question

In the figure below not to scale), let L-1.20 m and d = 0.160 mm and assume the slit system is illuminated with monochromatic Onm igt. S2 Viewing screen (a) Calculate the phase difference between the two wave fronts arriving at P when θ = 0.500 rad (b) Calculate the phase difference between the two wave fronts arriving at P when y- 5.00 mm. rad (c) What is the value of 0 for which the phase difference is 0.333 rad? (d) What is the value of 0 for which the path difference is A / 4?

Answer 1

Phase difference, phi = 2 pi/lambda d sin phi Given lambda = 540 nm = 540 times 10^- 9 m d = 0. 160mm = 0. 16 times 10^- 3 m Therefore phi = 2 pi/540 times 10^- 9 0. 16 times 10^- 3 times sin (0. 5) = 16 - 25 rad B) phi = 2 pi/lambda d(y/L) given y = 5. 00mm = 5 times 10^- 3, L = 1. 20m phi = 2 pi/540 times 10^- 9 0. 16 times 10^- 3 times (5 times 10^- 3/1. 20m) = 7. 76 red c) if phi = 0. 333 rad, = 2 pi d sin theta/lambda sin theta = phi lambda/2 pi d theta = sin^- 1 (2 phi d) = sin^- 1[540 times 10^- 9 times 0. 333]