The Young's double slit experiment, angular width of fringes is 0.20 radians for sodium light of wavelength 5890 Å . If the complete system is dipped in water, then the angular width of fringes will be [Refractive index of water .= 4 3 ]

Step-by-step solution

Angular fringe width is given by = d =0.2 radians = d If dipped in water ^ = ^ d where ^ = for water, = 4 3 Taking ratio of eq ^ n (1) and eq ^ n (2) aligned & 0.2 ^ = ( d ) ( 3 4 d ) & ^ =0.2 3 4 radians =0.15 radians aligned