Class 11 Physics · Chapter 8 · Test 2
Malus's Law and Polarization
35 MCQs This test covers Malus’s law (I = I₀cos²θ), the amplitude form A = A₀cosθ, extreme cases, and numericals with one or two polaroids. It also covers optical activity and the factors affecting rotation, and the importance and applications of polarization, including sunglasses, glare, sky photography and stress analysis.
35 questions · 30 min · 35 marks
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Sample questions
The first 5 of 35. Try each one, then tap to see the answer.
Question 1
Malus's law states that the intensity of plane polarized light passing through an analyzer is directly proportional to the:
- ASquare of the cosine of the angle between the transmission axes of the analyzer and polarizer
- BCosine of the angle between the two axes
- CSine of the angle between the two axes
- DTangent of the angle between the two axes
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Answer: A
Malus's law gives I proportional to cos²θ where θ is the angle between the transmission axes.
Question 2
The mathematical form of Malus's law is:
- AI = I₀ sin²θ
- BI = I₀ cosθ
- CI = I₀ cos²θ
- DI = I₀ / cos²θ
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Answer: C
I = I₀ cos²θ.
Question 3
In Malus's law the angle θ is the angle between the:
- ADirection of light and the analyzer
- BIncident ray and the reflected ray
- CIncident ray and the normal
- DTransmission axes of the polarizer and the analyzer
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Answer: D
θ is measured between the transmission axes of the analyzer and the polarizer.
Question 4
In Malus's law I₀ represents the intensity of the:
- AUnpolarized light before the polarizer
- BPlane polarized light incident on the analyzer
- CLight absorbed by the analyzer
- DLight transmitted by the analyzer
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Answer: B
I₀ is the intensity of the polarized light falling on the analyzer.
Question 5
An analyzer is a polaroid that is placed:
- ABefore the source of light
- BBehind the screen only
- CAfter a polarizer to study the polarized light
- DBetween the eye and the sun only
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Answer: C
An analyzer is placed after a polarizer and its orientation affects the intensity of polarized light.
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