English
Karnataka Board PUCPUC Science Class 11

In a Laser Tube, All the Photons

Advertisements
Advertisements

Question

In a laser tube, all the photons

Options

  • have same wavelength

  • have same energy

  • move in same direction

  •  move with same speed

MCQ
Advertisements

Solution

 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.

shaalaa.com
  Is there an error in this question or solution?
Chapter 43: Bohr’s Model and Physics of Atom - MCQ [Page 383]

APPEARS IN

HC Verma Concepts of Physics Volume 1 and 2 [English]
Chapter 43 Bohr’s Model and Physics of Atom
MCQ | Q 13 | Page 383

RELATED QUESTIONS

if `E_p` and `E_k` represent potential energy and kinetic energy respectively, of an orbital electron, then, according to B9hr's theory:

a)`E_k = -E_p"/"2`

b) `E_k = -E_p`

c) `E_k = -2E_p`

d) `E_k = 2E_p`

 


On the basis of Bohr's theory, derive an expression for the radius of the nth orbit of an electron of the hydrogen atom.


State Bohr postulate of hydrogen atom that gives the relationship for the frequency of emitted photon in a transition.


The electron in hydrogen atom is initially in the third excited state. What is the maximum number of spectral lines which can be emitted when it finally moves to the ground state?


The numerical value of ionization energy in eV equals the ionization potential in volts. Does the equality hold if these quantities are measured in some other units?


Which of the following parameters are the same for all hydrogen-like atoms and ions in their ground states?


According to Maxwell's theory of electrodynamics, an electron going in a circle should emit radiation of frequency equal to its frequency of revolution. What should be the wavelength of the radiation emitted by a hydrogen atom in ground state if this rule is followed?


A parallel beam of light of wavelength 100 nm passes through a sample of atomic hydrogen gas in ground state. (a) Assume that when a photon supplies some of its energy to a hydrogen atom, the rest of the energy appears as another photon. Neglecting the light emitted by the excited hydrogen atoms in the direction of the incident beam, what wavelengths may be observed in the transmitted beam? (b) A radiation detector is placed near the gas to detect radiation coming perpendicular to the incident beam. Find the wavelengths of radiation that may be detected by the detector.


When a photon is emitted by a hydrogen atom, the photon carries a momentum with it. (a) Calculate the momentum carries by the photon when a hydrogen atom emits light of wavelength 656.3 nm. (b) With what speed does the atom recoil during this transition? Take the mass of the hydrogen atom = 1.67 × 10−27 kg. (c) Find the kinetic energy of recoil of the atom.


What is the energy in joules released when an electron moves from n = 2 to n = 1 level in a hydrogen atom?


Ratio of longest to shortest wavelength in Balmer series is ______.


On the basis of Bohr's model, the approximate radius of Li++ ion in its ground state ifthe Bohr radius is a0 = 53 pm : 


According to Bhor' s theory the moment of momentum of an electron revolving in second orbit of hydrogen atom will be.


A set of atoms in an excited state decays ______.


The line at 434 nm in the Balmer series of the hydrogen spectrum corresponds to a transition of an electron from the nth to second Bohr orbit. The value of n is ______.


Write the ionisation energy value for the hydrogen atom.


The figure below is the Energy level diagram for the Hydrogen atom. Study the transitions shown and answer the following question:

  1. State the type of spectrum obtained.
  2. Name the series of spectrum obtained.


What is the velocity of an electron in the 3rd orbit of hydrogen atom if its velocity in the 1st orbit is v0?


Calculate the energy associated with third orbit of He+.


Energy and radius of first Bohr orbit of He+ and Li2+ are:

[Given RH = −2.18 × 10−18 J, a0 = 52.9 pm]


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×