0' ,
la)Fig. 43.(b)5.187. (a) The light with right-hand circular polarization (from
the observer's viewpoint) becomes plane polarized on passing through
a quarter-wave plate. In this case the direction of oscillations of
the electric vector of the electromagnetic wave forms an angle of
+45° with the axis 00' of the crystal (Fig. 43a); in the case of left-
hand polarization this angle will be equal to —45° (Fig. 43b).
(b) If for any position of the plate the rotation of the Polaroid
(located behind the plate) does not bring about any variation in
the intensity of the transmitted light, the initial light is natural;
if the intensity of the transmitted light varies and drops to zero,
the initial light is circularly polarized; if it varies but does not
drop to zero, then the initial light is composed of natural and cir-
cularly polarized light.
5.188. (a) Ax = 1 / 2 k (n, — no) (), (b) d (74 — n'e)
= —2 (71, — no) 06x < 0.
5.189. An = aX/n = 0.71.10-4, where a is the rotational con-
stant.
5.190. a = n/Ax tan 0 = 21 ang. deg./mm, /(x) cost (nx/Ax),
where x is the distance from the maximum.
5.191. dmin = (1/a) arcsin = 3.0 mm.
5.192. 8.7 mm.
5.193. [a] = 72 ang. deg./(dm•g/cm 3 ).
5.194. (a) Emi r, = 111/ 4B1 = 10.6 kV/cm; (b) 2.2.10 8 inter-
ruptions per second.
5.195. An = 2cHV/0), where c is the velocity of light in vacuum.
5.196. V = (^1) /2 (9)1 — (P 2 )/1H = 0.015 ang. min/A.
5.197. If one looks toward the transmitted beam and counts the
positive direction clockwise, then q = (a — VNH) 1, where N is
the number of times the beam passes through the substance (in
Fig. 5.35 the number is N = 5).
5.198. H min = 1tl4V1 = 4.0 kA/m, where V is the Verdet con-
stant. The direction along which the, light is transmitted changes
to the opposite.
5.199. t = mcwolkI = 12 hours. Although the effect is very small,
it was observed both for visible light and for SHF radiation.