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Question
Why is the diffraction of sound waves more evident in daily experience than that of light wave?
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Solution
The frequencies of sound waves lie between 20 Hz to 20 kHz, their wavelength ranges between 15 m to 15 mm. The diffraction occurs if the wavelength of waves is nearly equal to slit width.
The wavelength of light waves is 7000 × 10–10 m to 4000 × 10–10 m. For observing diffraction of light we need a very narrow slit width. In daily life experience, we observe the slit width very near to the wavelength of sound waves as compared to light waves. Thus, the diffraction of sound waves is more evident in daily life than that of light waves.
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