Gives the definition of metre in terms of wavelength of red cadmium light ___________________?
Correct answer: C. Michelson
- A. Newton
- B. Einstein
- C. Michelson
- D. Galileo
Explanation
Albert A. Michelson used the known wavelength of red cadmium light in precision measurements of the metre. The likely wrong choice is b, Einstein, because Einstein is strongly associated with light and relativity, but he did not make this metre definition.
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Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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