Refraction through Prism - UNSOLVED PRACTICE SET
Chapter: Ray Optics and Optical Instruments | Topic: Refraction through Prism
REFRACTION THROUGH PRISM - UNSOLVED PRACTICE SET
Topic: Refraction through Prism
Multiple Choice Questions
Q1. The angle of deviation produced by a prism depends on:
- Only the angle of the prism
- Only the refractive index of the prism material
- Both the angle of the prism and the refractive index
- Only the wavelength of light
Q2. For a prism in the position of minimum deviation:
- The angle of incidence is maximum
- The refracted ray inside the prism is parallel to the base
- The angle of emergence is zero
- The deviation is maximum
Q3. The refractive index of the material of a prism in terms of the angle of prism A and angle of minimum deviation D_m is:
- n = sin(A/2) / sin((A + D_m)/2)
- n = sin((A + D_m)/2) / sin(A/2)
- n = sin(A + D_m) / sin A
- n = sin A / sin D_m
Q4. In the position of minimum deviation for an equilateral prism:
- i₁ = i₂ and r₁ = r₂
- i₁ = 2i₂
- r₁ = 2r₂
- i₁ = 0
Q5. The deviation produced by a thin prism is given by:
- δ = (n − 1)A
- δ = nA
- δ = A/n
- δ = n/A
Q6. For a given prism, the angle of minimum deviation is:
- Different for different colors of light
- The same for all colors
- Zero for all colors
- Maximum for red light
Short Answer Questions
Q7. Define angle of deviation for a prism. Draw a ray diagram showing the deviation of light through a prism.
Q8. What is the position of minimum deviation? What are the special features of light passing through a prism in this position?
Q9. Why does a prism deviate light towards its base? Explain with a ray diagram.
Q10. A prism produces a minimum deviation of 30° for a certain wavelength. The angle of the prism is 60°. Calculate the refractive index of the prism material.
Q11. Why does the deviation produced by a prism depend on the wavelength of light? What does this lead to?
Q12. Explain why the angle of minimum deviation is different for different colors of light passing through the same prism.
Long Answer Questions
Q13. Derive the expression for the refractive index of the material of a prism in terms of the angle of the prism and the angle of minimum deviation. State the assumptions made.
Q14. With the help of a ray diagram, explain the refraction of light through a prism. Show that the angle of deviation δ = i₁ + i₂ − A, where A is the angle of the prism.
Q15. Explain the variation of angle of deviation with angle of incidence for a prism. Draw the i-δ curve and explain how the position of minimum deviation is determined from it...
Numerical & Application-Based Problems
Q16. A prism has an angle of 60° and refractive index 1.5. A ray of light enters the prism at an angle of incidence of 45°.
(a) Calculate the angle of refraction at the first surface.
(b) Calculate the angle of incidence at the second surface.
(c) Determine whether the ray will emerge from the prism or undergo total internal reflection.
(d) If it emerges, calculate the angle of emergence.
Q17. The angle of minimum deviation for an equilateral prism is 37°.
(a) Calculate the refractive index of the prism material.
(b) Calculate the angle of incidence at minimum deviation.
(c) If the prism is immersed in water (refractive index 4/3), what will be the new angle of minimum deviation?
Q18. In your school's physics lab, a student is given a hollow prism and asked to fill it with different liquids to study refraction.
(a) The hollow prism has an angle of 60°. When filled with water (n = 4/3), the angle of minimum deviation is measured as 10°. Calculate the refractive index of water using the prism formula and verify it.
(b) The student then fills the prism with an unknown liquid and measures the angle of minimum deviation as 15°. Calculate the refractive index of the liquid.
(c) The student repeats the experiment with a solid glass prism (n = 1.5, A = 60°) and finds D_m = 37°. A classmate claims that if the prism angle were doubled to 120°, the minimum deviation would also double to 74°. Evaluate this claim using the prism formula.
(d) Prisms are used in periscopes of submarines instead of mirrors. Discuss one advantage and one disadvantage of using prisms over mirrors in this application.