ICS Part 2 Physics Chapter 20 Short Questions Preparation

Question # 1

What is CAT scanner?

Ans 1: A vastly improved x-rays technique is computerized axial tomography: the corresponding instrument is called CAT scanner.In CAT scanning a number of different orientations.Computer is attached to construct picture,Density difference of the order of one percent can be detected,Tumors and other anomalies much too small to be seen with older techniques can be detected.

Question # 2

Write use of x-rays.

Ans 1: X-rays are used
1. To visualize the interior of the material opaque to ordinary light.
2. In computerized axial tomography.
3. In photographic films.

Question # 3

Can the electron in the ground state of hydrogen atom absorb a photon of energy 13.6 eV greater than 13.6 eV?

Ans 1: Yes an electron in the ground state of hydrogen atom can absorb a photon of energy 13.6 eV and greater than 13.6 eV.
ionization energy of hydrogen atom in ground state is 13.6 eV.So if hydrogen absorb a photon of energy greater than 13.6 eV than the surplus energy of photon appear as K.E of electron

Question # 4

What do we mean when we say that the atom is excited?

Ans 1: When energy from some external source is provide to an atom in its normal state,then its electron will jump from lower energy state to higher energy state.And atom is said to be excited.

Question # 5

Distinguished between stimulated emission and spontaneous emission.

Ans 1: Stimulated emission: If a atom is excited for a longer lifetime of about 10^-3sec than an incident photon of energy equal to the difference of two energy levels induces the atom to decay by emitting a photon that travel in the direction of incident photon.This process is called stimulated or induced emission.
Ans 2: Spontaneous Emission: As excited is highly unstable with life time of
10^-8sec,so electron will de excite itself with emission of a photon in any arbitrarydirection is called spontaneous emission.

Question # 6

Write down use of laser in industry.

Ans 1: It can be used for telecommunication in fibre optics.
It is used to read bar codes,
It is used to generate 3D image of objects by holography.

Question # 7

Differentiate between Line and Band spectrum.

Ans 1: Line spectrum: When electron jumps from higher orbit to lower orbit ,it emits energy,This emission of energy constitutes spectral line,This is called the line spectrum.
Ans 2: Band spectrum:is produced by molecules,They are the groups of lines which are closely spaced to another.

Question # 8

Explain why laser action could not occur without population inversion between atomic levels?

Ans 1: When a large percentage of atom or sample are in population inversion,then large number of coherent photons along same direction of motion could be obtained to form laser light,It is impossible withput population inversion.

Question # 9

Can x-rays be reflected,diffracted polarized just like any other eaves?Explain

Ans 1: Yes x rays can be reflected,refracted diffracted by crystal only and polarized just like any other waves.

Question # 10

Define continuous spectrum.

Ans 1: The radiation emitted by continuous media such as ''Black Body" forms a continuous spectrum,In continuousspectrum wavelengths of radiations can not be observed in discrete lines.

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ICS Part 2 Physics Chapter 20 Short Questions Preparation

12th Class PhysicsShort Questions Preparation

12th Class Physics Chapter Wise Preparation

Online Short Questions For Chapter 9 "ICS Part 2 Physics Chapter 20 Short Questions Preparation "

Physics - ICS Part 2 Physics Chapter 20 Short Questions Preparation

What is CAT scanner?

Write use of x-rays.

Can the electron in the ground state of hydrogen atom absorb a photon of energy 13.6 eV greater than 13.6 eV?

What do we mean when we say that the atom is excited?

Distinguished between stimulated emission and spontaneous emission.

Write down use of laser in industry.

Differentiate between Line and Band spectrum.

Explain why laser action could not occur without population inversion between atomic levels?

Can x-rays be reflected,diffracted polarized just like any other eaves?Explain

Define continuous spectrum.

Prepare Complete Set Wise Questions For Chapter 9 "ICS Part 2 Physics Chapter 20 Short Questions Preparation "

Set 1

Set 2

Set 3

ICS Part 2 Physics Chapter 20 Short Questions Preparation - Set 1

What is CAT scanner?

Write use of x-rays.

Can the electron in the ground state of hydrogen atom absorb a photon of energy 13.6 eV greater than 13.6 eV?

What do we mean when we say that the atom is excited?

Distinguished between stimulated emission and spontaneous emission.

Write down use of laser in industry.

Differentiate between Line and Band spectrum.

Explain why laser action could not occur without population inversion between atomic levels?

Can x-rays be reflected,diffracted polarized just like any other eaves?Explain

Define continuous spectrum.

ICS Part 2 Physics Chapter 20 Short Questions Preparation - Set 2

Write two postulate of Bohr's model of H-atom.

What is meant by line spectrum? How line spectrum can be used for the identification of elements?

Can electron reside inside the nucleus?

Can x-rays be reflected,diffracted polarized just like any other eaves?Explain

Define characteristics of X-rays and continuous x-rays.

What are the difference between laser light and ordinary light?

In which region of electromagnetic spectrum does the following series fall (a)Lyman series (b)Balmer series?

Define normal population and population inversion.

Is energy conserved when an atom emits a photon of light?

Briefly describe continuous x-rays.

ICS Part 2 Physics Chapter 20 Short Questions Preparation - Set 3

How does a Kax-rays differ KbX-rays?

Define continuous spectrum.

What are the advantages of laser over ordinary light?

Write two postulate of Bohr's model of H-atom.

Define normal population and population inversion.

What do we mean when we say that the atom is excited?

What is meant by line spectrum? How line spectrum can be used for the identification of elements?

What is fluorescence?

What do you mean by inner shell transition?

How can spectrum of hydrogen contain so many lines,whereas hydrogen atom contain one electron?

ICS Part 2 Physics Chapter 20 Short Questions Preparation

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12th Class Physics
Short Questions Preparation

How does a K_ax-rays differ K_bX-rays?