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प्रश्न
Let us list some of the factors, which could possibly influence the speed of wave propagation:
(i) Nature of the source
(ii) Direction of propagation
(iii) Motion of the source and/or observer
(iv) Wavelength
(v) Intensity of the wave
On which of these factors, if any, does the speed of light in vacuum?
उत्तर
The speed of light in a vacuum i.e., 3 × 108 m/s (approximately) is a universal constant. It is not affected by the motion of the source, the observer, or both. Hence, the given factor does not affect the speed of light in a vacuum.
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