Q29.Unpolarised light of intensity 32 W m−2 passes through the combination of three polaroids such that the pass axis of the last polaroids is perpendicular to that of the pass axis of first polaroids. If intensity of emerging light is 3 W m−2, then the angle between pass axis of first two polaroids is _________°.
What This Question Tests
This question involves applying Malus's Law successively for three polaroids to find the angle between the first two polaroids, given the initial unpolarised light intensity and the final emerging intensity.
Concepts Tested
Formulas Used
I = I₀ cos²θ
I = I₀/2 (for unpolarised light through first polaroid)
📚 NCERT Sections This Tests
10.5 — In Young’S Double-Slit Experiment Using Monochromatic Light Of
Physics Class 12 · Chapter 10
10.5 In Young’s double-slit experiment using monochromatic light of wavelength l, the intensity of light at a point on the screen where path difference is l, is K units. What is the intensity of light at a point where path difference is l/3?
9.6 — A Prism Is Made Of Glass Of Unknown Refractive Index. A Parallel
Physics Class 12 · Chapter 9
9.6 A prism is made of glass of unknown refractive index. A parallel beam of light is incident on a face of the prism. The angle of minimum deviation is measured to be 40°. What is the refractive index of the material of the prism? The refracting angle of the prism is 60°. If the prism is placed in water (refractive index 1.33), predict the new angle of minimum deviation of a parallel beam of light.
9.4 — Figures 9.27(A) And (B) Show Refraction Of A Ray In Air Incident At 60°
Physics Class 12 · Chapter 9
9.4 Figures 9.27(a) and (b) show refraction of a ray in air incident at 60° with the normal to a glass-air and water-air interface, respectively. Predict the angle of refraction in glass when the angle of incidence in water is 45° with the normal to a water-glass interface [Fig. 9.27(c)]. FIGURE 9.27
📋 Question Details
- Chapter
- Wave Optics
- Topic
- Polarization by Polaroid Sheets
- Year
- 2023
- Shift
- 10 Apr Shift 1
- Q Number
- Q29
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 10: Wave Optics
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