Question

lightstrikes a flat 2.00cm thick block of glass (n-1.50) at an angle of 30.0 with the normal Fig. ). (o) Trnce the light beam through the glass, incidence and refnction at each surfince. (b)When the light glass, block, it is required for the light to pass through the glass block ray passes through the shifted laterally by a distance d. Find the value of d.(c) Find the time 30.0 2.00 cm

Answer 1

r = refracted ray At surface (1) I = 30 degree n_1 = 1, n_2 = 1.5 sin I/sin r = n_2/n_1 sin r = sin I times n_1/n_2 = 1/2 times 1/1.5 = 1/3 r = sin^-1 (1/3) at surface (2) angle I = angle r = sin^-1(1/3) = 19.47 angle e rightdoublearrow sin e = sin r times n_2/n_1 = 1/3 times 3/2 = 1/2 angle e = 30 degree tan r = x/2 tan 30 degree = x + d/2 x/tan r = x + d/tan 30 degree x/0.3535 = x + d/ 0.577 0.707 times 0.577 = (0.707 + d) 0.3535 0.407939 = 0.2499 + 0.3535d 0.158 = 0.3535 d d = 0.447 cm (c) t = distance covered/velocity in medium = l/cos r times 1/v velocity v = c/n_2 = 3 times 10^8/1.5 = 2 times 10^8 m/s