Question 6: Ray Optics

Question

A thin prism $$P_1$$ of angle $$4^{\circ}$$ and refractive index 1.54 is combined with another prism $$P_2$$ of refractive index 1.72 produce dispersion without deviation, the angle of $$P_2$$ is

Accepted Answer

Given, angle of prism $$P_1=4^{\circ}$$
$$\begin{aligned}
P_2 & =? \
\eta_1 & =1.54 \
\eta_2 & =1.72
\end{aligned}$$
Angle of deviation $$\delta=(n-1) A$$
Dispersion produced by both the prism will be equal
$$\begin{aligned}
	ext { i.e. } & \left(n_1-1ight) A_1=\left(n_2-1ight) A_2 \
\Rightarrow \quad A_2 & =\frac{\left(n_1-1ight) A_1}{\left(n_2-1ight)}=\frac{(1 \cdot 54-1) 	imes 4}{(1 \cdot 72-1)} \
& =3^{\circ}
\end{aligned}$$
Hence, the angle of prism $$P_2$$ is $$=3^{\circ}$$

Answer

$$4^{\circ}$$

Answer

$$5.33$$

Answer

$$2.6^{\circ}$$

Answer

$$3^{\circ}$$

Ray Optics

A thin prism $P_1 of angle 4^{\circ} and refractive index 1.54 is combined with another prism P_2 of refractive index 1.72 produce dispersion without deviation, the angle of P_2$ is

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