ICS Part 2 Physics Chapter 20 Short Questions Preparation

Question # 1

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

Ans 1: The single electron in hydrogen atom occupies ground state but it can be excited to several states by absorbing energy.During de-excitation ,it can emit several lines of different wavelength.

Question # 2

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 # 3

How does a K_ax-rays differ K_bX-rays?

Ans 1: When an electron from L -shell jumps to occupy the hole in K- shell K_ax-rays is emitted .
And
When an electron from M -shells jumps to occupy the hole in K-Shell K_bX-rays is emited.

Question # 4

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 # 5

Define population inversion and metastable stable.

Ans 1: A condition of matter in which more electrons are in a high energy state than in a lower energy state is called population inversion.
A particular excited state of an atom that has longer lifetime than the ordinary excited states is called metastable state.

Question # 6

Briefly describe continuous x-rays.

Ans 1: Continuous X-rays is due to an effect known as Bremsstrahlung effect when fast moving electron bombarded at the target,they are suddenly slowed down on impact with the target,And due to deceleration their kinetic energy is converted into X-rays photons.

Question # 7

What is fluorescence?

Ans 1: Fluorescence is a property of absorbing radiant energy of high frequency and re emitting energy of low frequency in the visible region of electromagnetic spectrum.

Question # 8

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

Ans 1: Balmer series falls in the visible region.
Lyman series falls in the ultraviolet region.

Question # 9

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 # 10

Define normal population and population inversion.

Ans 1: In normal population ,the lower energy state has a greater population than the higher energy state.
Population inversion occurs when no more electron are in a higher energy state than in lower energy state.

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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

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

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

How does a Kax-rays differ KbX-rays?

Differentiate between Line and Band spectrum.

Define population inversion and metastable stable.

Briefly describe continuous x-rays.

What is fluorescence?

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

Distinguished between stimulated emission and spontaneous emission.

Define normal population and population inversion.

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

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

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

How does a Kax-rays differ KbX-rays?

Differentiate between Line and Band spectrum.

Define population inversion and metastable stable.

Briefly describe continuous x-rays.

What is fluorescence?

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

Distinguished between stimulated emission and spontaneous emission.

Define normal population and population inversion.

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

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

Briefly describe continuous x-rays.

Write two properties of x-rays.

What do you mean by inner shell transition?

what is Spectroscopy?

What are the advantages of laser over ordinary light?

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

Define population inversion and metastable stable.

Write down use of laser in industry.

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

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

Define population inversion and metastable stable.

Define normal population and population inversion.

Bohr's theory of hydrogen atom is based upon several assumptions.Do any of these assumptions contradict classical physics?

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

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

Write two properties of x-rays.

Give two uses of laser in medicine and industry.

List of color of line spectra of an excited hydrogen atom.

What is fluorescence?

what is Spectroscopy?

ICS Part 2 Physics Chapter 20 Short Questions Preparation

12th Class Physics
Short Questions Preparation

How does a K_ax-rays differ K_bX-rays?

How does a K_ax-rays differ K_bX-rays?