CBSE Physics Physical Optics Expected Questions : Unit IX
Short Answer Type Question
Q. 1, Show how wavefront behaves while passing through a prism, a lens and a mirror. Ans. Behaviour of a wave front
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Q. 2. Why are two bulbs lighting the same walls considered as incoherent sources ? How do their intensities add up ?
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Q. 3. State and explain the principle of superposition of waves.
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Q. 4. What are the necessary conditions for producing sustained interference 7
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Q. 5. Why is the diffraction of sound more evident in daily life than that of the light waves ?
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Q. 6. Why does the electric field of an electromagnetic wave determine its polarisation rather than the magnetic field ?
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Q. 7. Explain polarisation affords a convincing evidence of transverse nature of light.
Q. 8. In a Young’s double slit experiment, the slits are separated by 0.03 cm and the screen is placed 1.5 m away. The distance between the central fringe and the fourth bright fringe is 1 cm-Determine the wavelength of light used in the experiment.
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