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Bohr's Postulates

The French ph...

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The French physicist, de Broglie, in 1924 proposed that matter, like radiation, should also ? exhibit dual behaviour i.e., both particle and wavelike properties. This means that just as the photon has momentum as well as wavelength, electrons should also have momentum as well ? as wavelength. De Broglie gave a relation between wavelength and momentum ?
Q1.What is de Broglie?s relation? ?
Q2.Why are de Broglie?s wavelength associated with a moving football is not visible?

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Solution

Dear student,

Ans-1 The de Broglie equation is:
λ = h/mv
where,
λ is wavelength, h is Planck's constant, m is the mass of a particle, moving at a velocity v.
p(momentum) = mv
λ = h/p

Ans-2 De Broglie's wavelength is not visible with a moving football because of its large mass , the wavelength associated is very small. So, its wave nature is not visible.

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The French physicist Louis de Broglie in 1924 postulated that matter, like radiation, should exhibit a dual behavior. He proposed the following relationship between the wavelength

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The de Broglie relation implies that the wavelength of a particle should decrease as its velocity increases. It also implies that for a given velocity heavier particles should have a shorter wavelength than lighter particles. The waves associated with particles in motion are called matter waves or de-Broglie waves. These waves differ from the electromagnetic wave as they
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The experimental confirmation of the de Broglie relation was obtained when Davisson and Germer, in 1927, observed that a beam of electrons is diffracted by a nickel crystal. As diffraction is a characteristic property of waves, hence the beam of electron behaves as a wave, as proposed by de Broglie.

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Q. The French physicist Louis de Broglie in 1924 postulated that matter, like radiation, should exhibit a dual behaviour. He proposed the following relationship between the wavelength lambda of a material particle, its linear momentum p and planck constant h.

λ = \frac{h}{p} = \frac{h}{m v}

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The experimental confirmation of the de Broglie’s relation was obtained when Davisson and Germer, in 1927, observed that a beam of electrons is diffracted by a nickel crystal. As diffraction is a characteristic property of waves, hence the beam of electron behaves as a wave, as proposed by de Broglie.

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The French physicist Louis de Broglie in 1924 postulated that matter, like radiation, should exhibit a dual behaviour. He proposed the following relationship between the wavelengh

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of a material particle, its linear momentum p and planck constant h.

λ = \frac{h}{p} = \frac{h}{m v}

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(i) have lower velocities
(ii) have no electrical and magnetic fields and
(iii) are not emitted by the particle under consideration.
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