A thin prism $P_1$ with an angle $6^{\circ}$ and made of glass of refractive index $1.54$ is combined with another prism $P_2$ made from glass of refractive index $1.72$ to produce dispersion without average deviation. The angle of prism $P_2$ is
Solution
<p>$({\mu _1} - 1){A_1} = ({\mu _2} - 1){A_2}$</p>
<p>$\Rightarrow (1.54 - 1)6 = (1.72 - 1){A_2}$</p>
<p>$${A_2} = \left( {{{0.54} \over {0.72}} \times 6} \right) = {{18} \over 4} = \left( {{9 \over 2}} \right) = 4.5^\circ $$</p>
About this question
Subject: Physics · Chapter: Optics · Topic: Refraction and Snell's Law
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