NEET-XII-Physics

43: Bohr's Model and Physics of the Atom

with Solutions - page 2
Qstn# ii-13 Prvs-QstnNext-Qstn
  • #13
    In a laser tube, all the photons
    (a) have same wavelength
    (b) have same energy
    (c) move in same direction
    (d) move with same speed
    digAnsr:   d
    Ans : (d) 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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