Cathode rays are similar to visible light rays in that

  • They both can be deflected by electric and magnetic fields

  • They both have a definite magnitude of wavelength

  • They both can ionize a gas through which they pass

  • They both can expose a photographic plate

Electron volt is a unit of 

  • Potential                         

  • Charge

  • Power                             

  • Energy

In an electron gun, the electrons are accelerated by the potential V. If e is the charge and m is the mass of an electron, then the maximum velocity of these electrons will be

  •  2eVm                   

  •  2eVm

  •  2meV                 

  •  V22em

The idea of matter waves was given by

  • Davisson and Germer                 

  • de-Broglie

  • Einstein                                     

  • Planck

Wave is associated with matter:

  • when it is stationary.

  • when it is in motion with the velocity of light only.

  • when it is in motion with any velocity.

  • None of the above.

The de-Broglie wavelength associated with the particle of mass m moving with velocity v is

  • h/mv                 

  • mv/h 

  • mh/v                 

  • m/hv

A photon, an electron, and a uranium nucleus all have the same wavelength. The one with the most energy: 

  • Is the photon

  • Is the electron

  • Is the uranium nucleus

  • Depends upon the wavelength and the properties of the particle

A particle which has zero rest mass and non-zero energy and momentum must travel with a speed:

  • equal to c, the speed of light in vacuum.

  • greater than c.

  • less than c.

  • tending to infinity.

When the kinetic energy of an electron is increased, the wavelength of the associated wave will

  • Increase

  • Decrease

  • Wavelength does not depend on the kinetic energy

  • None of the above

If the de-Broglie wavelengths for a proton and for an α-particle are equal, then the ratio of their velocities will be:

  • 4 : 1
  • 2 : 1
  • 1 : 2
  • 1 : 4

The de-Broglie wavelength λ associated with an electron having kinetic energy E is given by the expression

  •  h2mE                           

  •  2hmE

  •  2mhE                               

  •  22mEh

Dual nature of radiation is shown by:

  • Diffraction and reflection

  • Refraction and diffraction

  • Photoelectric effect alone

  • Photoelectric effect and diffraction

The momentum of a photon in an X-ray beam of 10-10 metre wavelength is 

  • 1.5×10-23  kg-m/sec

  • 6.6×10-24 kg-m/sec

  • 6.6×10-44 kg-m/sec

  • 2.2×10-52  kg-m/sec

An electron of mass m when accelerated through a potential difference V has de-Broglie wavelength λ. The de-Broglie wavelength associated with a proton of mass M accelerated through the same potential difference will be

  •  λmM                           

  • λmM

  • λMm                           

  • λMm

What is the de-Broglie wavelength of the α-particle accelerated through a potential difference V 

  • 0.287V Å                 

  • 12.27V Å

  •  0.101V Å                 

  • 0.202V Å

The energy that should be added to an electron, to reduce its de-Broglie wavelengths from 10-10 m to 0.5×10-10 m, will be:

  • four times the initial energy.

  • thrice the initial energy.

  • equal to the initial energy.

  • twice the initial energy.

The de-Broglie wavelength of an electron having 80eV of energy is nearly
(1eV =1.6×10-19 J, Mass of electron = 9×10-31Kg Plank’s constant = 6.6×10-34 J-sec)

  • () 140 Å                     
  • () 0.14 Å
  • () 14 Å                       
  • () 1.4 Å

If particles are moving with same velocity, then maximum de-Broglie wavelength will be for 

  • Neutron               

  • Proton

  • β-particle             

  • α-particle

If an electron and a photon propagate in the form of waves having the same wavelength, it implies that they have the same 

  • Energy             

  • Momentum

  • Velocity             

  • Angular momentum

The de-Broglie wavelength is proportional to 

  • λ1v               

  • λ1m

  • λ1p               

  •  λp

Particle nature and wave nature of electromagnetic waves and electrons can be shown by 

  • Electron has small mass, deflected by the metal sheet

  • X-ray is diffracted, reflected by thick metal sheet

  • Light is refracted and defracted

  • Photoelectricity and electron microscopy

The de-Broglie wavelength of a particle moving with a velocity 2.25×108 m/s is equal to the wavelength of the photon. The ratio of the kinetic energy of the particle to the energy of the photon is (velocity of light is 3×108 m/s)

  • 1/8                   

  • 3/8

  • 5/8                   

  • 7/8

The speed of an electron having a wavelength of 10-10m is

  • () 7.25×106 m/s                   
  • () 6.26×106 m/s 
  • () 5.25×106 m/s                   
  • () 4.24×106 m/s

The kinetic energy of electron and proton is 10-32 J. Then the relation between their de-Broglie wavelengths is

  •  λp<λe                 

  • λp>λe

  •  λp=λe                 

  • λp=2λe

The de-Broglie wavelength of a particle accelerated with 150 volt potential is 10-10 m. If it is accelerated by 600 volts p.d., its wavelength will be

  • 0.25 Å                 

  • 0.5 Å

  • 1.5 Å                   

  • 2 Å

The de-Broglie wavelength associated with a hydrogen molecule moving with a thermal velocity of 3 km/s will be

  • 1 Å                     

  • 0.66 Å

  • 6.6 Å                 

  • 66 Å

When the momentum of a proton is changed by an amount P0, the corresponding change in the de-Broglie wavelength is found to be 0.25%. Then, the original momentum of the proton was 

  • () P0                  
  • () 100  P0
  • () 400 P0            
  • () 4 P0

The de-Broglie wavelength of a neutron at 27 °C is λ. What will be its wavelength at 927 °C

  • () λ / 2                       
  • () λ / 3
  • () λ / 4                       
  • () λ / 9

An electron and proton have the same de-Broglie wavelength. Then the kinetic energy of the electron is

  • Zero

  • Infinity

  • Equal to the kinetic energy of the proton

  • Greater than the kinetic energy of the proton

For moving ball of cricket, the correct statement about de-Broglie wavelength is

  • It is not applicable for such big particle

  • h2mE

  • h2mE

  • h2mE

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