The standard meter was defined by Michelson using light emitted from:
Correct answer: B. Cadmium
- A. Cesium
- B. Cadmium
- C. Platinum
- D. Gold
Explanation
The correct option is B because The standard meter was originally defined in terms of the wavelength of a particular spectral line of cadmium, specifically the red cadmium line at 6438.4696 angstroms. This definition was later replaced by the definition based on the speed of light.
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About Optics
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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