Question # 1

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

Ans 1: Chararcterstics X-rays: The x-rays emitted from inner shell transitions are called characteristics x-rays and their energy depends on the type of target material.
Continuous X-rays:The x-rays emitted having continuous range of frequencies due to bremsstrahlung effect are called continuous x rays.

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

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.

Question # 4

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.

Question # 5

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 # 6

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 # 7

What are the advantages of laser over ordinary light?

Ans 1: Laser light has many advantages over ordinary light such as laser light is
1. Coherent
2. Intense
3. Monochromatic
4. Unidirectional

Question # 8

what is Spectroscopy?

Ans 1: It is that branch of physics which deals with the production,measurement and interaction of electromagnetic radiation emitted or absorbed by atom is called Spectroscopy.

Question # 9

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

Ans 1: The color of line spectrum of hydrogen atom are
- Red
- Blue
- Blue-Green
- Violet
- Ultraviolet

Question # 10

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.

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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

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

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

Define normal population and population inversion.

Define continuous spectrum.

Write down use of laser in industry.

Distinguished between stimulated emission and spontaneous emission.

What are the advantages of laser over ordinary light?

what is Spectroscopy?

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

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

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

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

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

Define normal population and population inversion.

Define continuous spectrum.

Write down use of laser in industry.

Distinguished between stimulated emission and spontaneous emission.

What are the advantages of laser over ordinary light?

what is Spectroscopy?

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

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

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

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

What is CAT scanner?

Write two properties of x-rays.

What are the difference between laser light and ordinary light?

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

Write down use of laser in industry.

what is Spectroscopy?

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

Define population inversion and metastable stable.

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

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

what is Spectroscopy?

What is meant by lasing action?

Define population inversion and metastable stable.

How does a Kax-rays differ KbX-rays?

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

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

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

Write down use of laser in industry.

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

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

How does a K_ax-rays differ K_bX-rays?