The width of the fringes obtained with a light of wave length 6.2 10⁻⁸ m is 1.82 mm. If the whole apparatus is immersed in a liquid of refractive index 1.3, what will be the width of the resulting fringe?

Step-by-step solution

The fringe width in air is given by = D d . When the apparatus is immersed in a liquid of refractive index , the wavelength of light in the liquid becomes ' = . The new fringe width is ' = ' D d = D d = . Given = 1.82 mm and = 1.3 . Substituting the values, ' = 1.82 1.3 = 1.4 mm. Answer: 1.4 mm