ICS Part 2 Physics Chapter 20 Short Questions Preparation

Question # 1

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 # 2

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

Ans 1:
- An electron ,bound to the nucleus in an atom,can moved around the nucleus in certain circular orbits without radiating,These orbits are called the discrete stationary orbits.
- Only those stationary orbits are allowed for which orbital angular momentum is equal to an integral multiple mvr=nh/2π.

Question # 3

What do you mean by inner shell transition?

Ans 1: A transition in which an electron from higher orbit,emits energy and accommodate a hole in the lower orbit.Such a transition is called inner shell transition.The photons emitted in such transition are called characteristic x-rays.

Question # 4

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 # 5

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 # 6

Give two uses of laser in medicine and industry.

Ans 1: Laser is used
1. For welding detached retinas
2. To destroy cancerous and precancerous cells.

Question # 7

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 # 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

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 # 10

Can electron reside inside the nucleus?

Ans 1: No,electron cannot reside inside the nucleus .If electron resides inside nucleus then uncertainty in position.

Latest Educational News Stories

Pakistan's Largest Database of Colleges and Universities

BS Programs

University Past Papers

University Results

Exam Results 2024

Study Abroad Programs and Opportunities for Pakistani Students

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

Differentiate between Line and Band spectrum.

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

What do you mean by inner shell transition?

Distinguished between stimulated emission and spontaneous emission.

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

Give two uses of laser in medicine and industry.

What is CAT scanner?

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

How does a Kax-rays differ KbX-rays?

Can electron reside inside the nucleus?

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

Differentiate between Line and Band spectrum.

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

What do you mean by inner shell transition?

Distinguished between stimulated emission and spontaneous emission.

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

Give two uses of laser in medicine and industry.

What is CAT scanner?

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

How does a Kax-rays differ KbX-rays?

Can electron reside inside the nucleus?

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

Write down use of laser in industry.

How does a Kax-rays differ KbX-rays?

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

Write use of x-rays.

Define normal population and population inversion.

Write two properties of x-rays.

Define population inversion and metastable stable.

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

What is CAT scanner?

What are the difference between laser light and ordinary light?

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

What do you mean by inner shell transition?

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

What are the difference between laser light and ordinary light?

Briefly describe continuous x-rays.

Write down use of laser in industry.

Differentiate between Line and Band spectrum.

Give two uses of laser in medicine and industry.

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

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

What are the advantages of laser over ordinary light?

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?

How does a K_ax-rays differ K_bX-rays?