Miscellaneous - NEET Physics Questions
Question 1: moderate

Two polaroids are placed in the path of unpolarized beam of intensity I0 such that no light is emitted from the second polaroid. If a third polaroid whose polarization axis makes an angle θ with the polarization axis of first polaroid, is placed between these polaroids then the intensity of light emerging from the last polaroid will be :

1. \[\left( \frac{I_{0}}{8} \right)sin^{2} 2\theta\]
2. \[\left( \frac{I_{0}}{4} \right)sin^{2} 2\theta\]
3. \[\left( \frac{I_{0}}{2} \right)cos^{2} \theta\]
4. \[I_{0}cos^{4} \theta\]
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Question 2: moderate

A light has amplitude A and angle between analyser and polariser is 60 degree. Light is transmitted by analyser has amplitude.

1. A√2
2. A/√2
3. √3 A/2
4. A/2
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Question 3: moderate

Two Nicols are oriented with their principal planes making an angle of 60°. The percentage of incident unpolarized light which passes through the system is :

1. 50%
2. 100%
3. 12.5%
4. 37.5%
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Question 4: moderate

The graph showing the dependence of intensity of transmitted light on the angle between polariser and analyser, is :

1.
2.
3.
4.
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Question 5: moderate

A beam of unpolarised light of intensity \(I_0\) is passed through a polaroid \(A\) and then through analyser \(B\) which is oriented such that its pass-axis makes an angle of \(30^\circ\) relative to that of \(A\). The intensity of emergent light is

1. \(frac{I_0}{4}\)
2. \(frac{3I_0}{8}\)
3. \(frac{3I_0}{4}\)
4. \(frac{I_0}{16}\)
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Intensity after polaroid \(A\) is \(I_1 = frac{I_0}{2}\). Using Malus's Law, the intensity after analyser \(B\) is \(I_2 = I_1 \cos^2 30^\circ = frac{I_0}{2} \left(\frac{\sqrt{3}}{2}\right)^2 = frac{3I_0}{8}\).