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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
Using Bohr's postulates of the atomic model, derive the expression for radius of nth electron orbit. Hence obtain the expression for Bohr's radius.
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The earth revolves round the sun due to gravitational attraction. Suppose that the sun and the earth are point particles with their existing masses and that Bohr's quantization rule for angular momentum is valid in the case of gravitation. (a) Calculate the minimum radius the earth can have for its orbit. (b) What is the value of the principal quantum number n for the present radius? Mass of the earth = 6.0 × 10−24 kg. Mass of the sun = 2.0 × 1030 kg, earth-sun distance = 1.5 × 1011 m.
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(ii) The emission spectrum of the Balmer series.
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State three postulates of Bohr's theory of hydrogen atom.
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What happens to an electron revolving in a circular orbit according to classical electromagnetic theory?
What does Bohr’s first postulate allow an electron in an atom to do?
Which expression gives the orbital frequency used to calculate the initial frequency of light emitted under classical electromagnetic theory?
