Angle of a thin prism – Rankers Physics

Refraction by Prism: Practice Problem & Solution

A ray of light is incident normally on one face of a thin prism of refractive index \(mu\) and emerges at an angle (e) from the normal. Angle of prism \(A\) is nearly
\(\frac{e}{mu}\)
\(\mu e\)
\(\frac{1-e}{\mu}\)
\(\mu\left(\frac{\pi}{2} - e\right)\)

Solution Explained:

To solve this problem, we apply the core principles of Refraction by Prism. Understanding the underlying formula is key to arriving at the correct answer below:

For normal incidence on the first face, the angle of refraction \(r_1 = 0\), which implies \(r_2 = A\). Applying Snell's law at the second face for small angles, \(e \approx \mu r_2 = \mu A\), giving \(A \approx \frac{e}{\mu}\).

Leave a Reply

Your email address will not be published. Required fields are marked *

Similar Practice Questions

Explore conceptually related problems to test your knowledge.

1. A star, which is emitting radiation at a wavelength of 5000 $\AA$, is approaching the earth with a velocity of $1.5 \times 10^4 m/s$. The change in wavelength of the radiation as received on the earth is: (1995)
2. Assertion (A): In clear weather, sky appears to be blue not violet. Reason (R): In clear atmosphere, light of shorter wavelength is scattered more as compared to light of longer wavelength.  
3. Assertion (A): Biconvex lens can form virtual image of a virtual object. Reason (R): Nature of lens depends on refractive index of surrounding.  
4. There is a prism with refractive index equal to $\sqrt{2}$ and the refractive angle equal to $30^\circ$. One of the refractive surface of the prism is polished. A beam of monochromatic light will retrace its path if its angle of incidence over the refracting surface of the prism is (1992)
5. Assertion (A): If an air bubble is trapped in a glass slab will not produce any lens action. Reason (R): Behaviour of a shape like a lens is in dependent of surrounding medium.