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प्रश्न
In a laser tube, all the photons
विकल्प
have same wavelength
have same energy
move in same direction
move with same speed
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उत्तर
move with same speed
All the photons emitted in the laser move with the speed equal to the speed of light (c = 3×108 m/s).
Ideally, the light wave through the laser must be coherent, but in practical laser tubes, there is some deviation from the ideal result. Thus, the photons emitted by the laser have little variations in their wavelengths and energies as well as the directions, but the velocity of all the photons remains same.
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संबंधित प्रश्न
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