Question 42: Waves Optics

Question

In Young's double slit experiment, the fringe width is found to be 0.4 mm. If the whole apparatus is immersed in a liquid of refractive index $$\frac{4}{3}$$ without changing geometrical arrangement, the new fringe width will be

Accepted Answer

If fringe widths of air and water are $$\beta_{\mathrm{air}}$$ and $$\mathrm{{\beta _{water}}}$$ respectively, then fringe width, $$\mathrm{{\beta _{water}} = {{{\beta _{air}}} \over \mu }}$$
Given, $$\mu  = {4 \over 3},{\beta _{air}} = 0.4$$
Hence, $${\beta _{water}} = {{0.4} \over {4/3}} = 0.3$$ mm

Answer

0.45 mm

Answer

0.4 mm

Answer

0.53 mm

Answer

0.30 mm

Waves Optics

In Young's double slit experiment, the fringe width is found to be 0.4 mm. If the whole apparatus is immersed in a liquid of refractive index $\frac{4}{3}$ without changing geometrical arrangement, the new fringe width will be

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