Tag: wave nature of matter

Questions Related to wave nature of matter

Who won the Nobel prize in physics in the year 1929 for the discovery of the wave nature of electrons?

  1. Erwin Schrodinger

  2. R.A Millikan

  3. Louis Victor de Brogue

  4. Albert Einstein


Correct Option: C
Explanation:
The Nobel price in physics $1929$ was awarded to prince Louis Vector "for the discovery of the wave nature of electrons, as he discovered the wave nature of electrons and suggested that all the matter have wave properties.

In Davisson-Germer experiment an electron beam of energy $60\ eV$ falls normally on the surface of a crystal. If the maximum intensity is obtained at an angle of $60^{\circ}$ to the direction of incident beam. then inter-atomic distance in the lattice plane of the crystal will be-

  1. $18\ A^{\circ}$

  2. $3.6\ A^{\circ}$

  3. $1.8\ A^{\circ}$

  4. $0.18\ A^{\circ}$


Correct Option: C

The idea of matter waves was given by

  1. Davisson and Germer

  2. de-Broglie

  3. Einstein

  4. Planck


Correct Option: B

Drift speed of electrons is of the order of- 

  1. zero

  2. ${ 10 }^{ -2 }$ cm/sec

  3. ${ 10 }^{ 5 }$ m/sec

  4. ${ 10 }^{ -4 }$ m/sec


Correct Option: D
Explanation:

Drift speed of electrons is of the order of ${10^{ - 4}}\,m/\sec $

Hence, the option $D$ is the correct answer.

In Davisson-Germer experiment electrons were made to strike a sheet made of ______ metal.

  1. Nickel

  2. Cobalt

  3. Iron

  4. Gold


Correct Option: A
Explanation:

Davisson and Germer experiment was conducted by two American scientists Clinton Davisson and Lester Germer, in 1927, to verify the de Broglie hypothesis that a material particle posses wave nature. 

The electron beam was made to pass through a hole and strike the nickel crystal normally, the electrons scattered in all directions acting like waves. The detector indicated the peak intensity of scattered electrons at certain angle. This maximum intensity was due to constructive interference of two waves. Thus wave nature of electrons was experimentally proved.

In Davisson-Germer experiment, electron gun is coated with oxide of _______ .

  1. Barium

  2. Sodium

  3. Potassium

  4. Iron


Correct Option: A
Explanation:

The Davisson and Germer experiment consisted of Nickel crystal (target), electron gun and a detector. The electron gun consisted of tungsten filament with high and low tension batteries. The work function of uncoated tungsten filament is 4.5 eV. The coating of Barium oxide on this filament reduces its work function so that electron can be emitted at low temperature.

In Davisson-Germer experiment, the electron beam is made to fall on surface of _________ crystals.

  1. Nickel

  2. Iron

  3. Gold

  4. Cesium


Correct Option: A
Explanation:

Davisson-Germer experiment was conducted by two American scientists Clinton Davisson and Lester Germer, in 1927, to verify the de Broglie hypothesis that a material particle posses wave nature. 

The electron beam was made to pass through a hole and strike the surface of nickel crystal normally, the electrons scattered in all directions acting like waves. The detector indicated the peak intensity of scattered electrons at certain angle. This maximum intensity was due to constructive interference of two waves. Thus wave nature of electrons was experimentally proved.

Davisson and Germer experiment represents _______ nature of the electron.

  1. Wave

  2. Particle

  3. Wave and particle

  4. Doesn't represent any nature


Correct Option: A
Explanation:

Davisson-Germer experiment was conducted by two American scientists Clinton Davisson and Lester Germer, in 1927, to verify the de Broglie hypothesis that a material particle posses wave nature. 

The electron beam was made to pass through a hole and strike the nickel crystal normally, the electrons scattered in all directions acting like waves. The detector indicated the peak intensity of scattered electrons at certain angle. This maximum intensity was due to constructive interference of two waves. Thus wave nature of electrons was experimentally proved.

Davisson Germer experiment explained the wave nature of electrons through 

  1. Electron diffraction

  2. Electron interference

  3. Electron scattering

  4. Failed to explain wave nature of electrons


Correct Option: A
Explanation:

Davisson-Germer experiment was conducted by two American scientists Clinton Davisson and Lester Germer, in 1927, to verify the de Broglie hypothesis that a material particle posses wave nature. They experimentally proved the wave nature of electron through diffraction of electron beam by a nickel crystal.

In experiment of Davisson-Germer, emitted electron from filament is accelerated throguh voltage $V$ then de-Broglie wavelength of that electron will be ________ m .

  1. $\cfrac { 2eVm }{ \sqrt { h } } $

  2. $\cfrac { \sqrt { h } }{ 2Vem } $

  3. $\cfrac { \sqrt { 2Vem } }{ h } $

  4. $\cfrac { h }{ \sqrt { 2Vem } } $


Correct Option: D
Explanation:

Kinetic energy of the electron will be due to the voltage supplied.

$\cfrac { 1 }{ 2 } m{ v }^{ 2 }=eV$
$v=\sqrt { \cfrac { 2eV }{ m }  } $

We know that the wavelength is obtained as:
$\lambda =\cfrac { h }{ mv } $
$\quad \lambda =\cfrac { h }{ m\sqrt { \cfrac { 2eV }{ m }  }  } =\cfrac { h }{ \sqrt { 2eVm }  } $