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Wave Optics — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsWave Optics1 Mark
Question
Assertion : A narrow pulse of light is sent through a medium. The pulse will retain its shape as it travels through the medium.
Reason : A narrow pulse is made of harmonic waves with a large range of wavelengths.
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Answer

(e) A narrow pulse is made of harmonic waves with a large range of wavelength. As speed of propagation is different for different wavelengths, the pulse cannot retain its shape while travelling through the medium.

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