Question

What physical quantity is the same for X-rays of wavelength 10–10 m, red light of wavelength 6800 Å and radio waves of wavelength 500m?
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Answer 1

→The physical quantity is same for X-rays of wavelength 10^-10 m,

→ Red light of wavelength 6800 Å

→and radio waves of wavelength 500 m is the speed of light in vacuum which is equal to 3×108 m/s. The speed of light in vacuum remains same for all wavelengths. This is because speed of light is independent of wavelength in the vacuum.

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