Plane polarised light is passed through a polaroid. On viewing through the polaroid, we find that when the polaroid is given one complete rotation about the direction of the light, one of the following is observed :
Correct answer: C. There is no change in intensity
- A. The intensity of light gradually decreases to zero and remains at zero
- B. The intensity of light gradually increases to a maximum and remains at maximum
- C. There is no change in intensity
- D. The intensity of light is twice maximum and twice zero
Explanation
When plane polarised light is passed through a polaroid, it remains unchanged in intensity when the polaroid is given a complete rotation. This is because the polaroid only allows light oscillating in a specific direction to pass through, and this property does not change with rotation.The other options do not accurately describe the behavior of light passing through a polaroid when rotated, making them incorrect.
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Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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