ICS Part 2 Physics Chapter 20 Short Questions Preparation

Question # 1

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 # 2

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 # 3

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 # 4

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 # 5

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

Ans 1: When an electron jumps from higher energy state to lower energy state than emits energy and make a spectral line.
E₂- E₁_=hf
_{This is called line spectrum.And different elements emit line spectrum of different wavelengths,So they can be identifiedeasily.}

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

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

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 # 9

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 # 10

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.

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ICS Part 2 Physics Chapter 20 Short Questions Preparation

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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

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

Distinguished between stimulated emission and spontaneous emission.

Briefly describe continuous x-rays.

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

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

Write down use of laser in industry.

What are the advantages of laser over ordinary light?

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

What is fluorescence?

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

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

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

Distinguished between stimulated emission and spontaneous emission.

Briefly describe continuous x-rays.

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

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

Write down use of laser in industry.

What are the advantages of laser over ordinary light?

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

What is fluorescence?

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

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

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?

Write down use of laser in industry.

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

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

Write two properties of x-rays.

Define continuous spectrum.

what is Spectroscopy?

How does a Kax-rays differ KbX-rays?

Define normal population and population inversion.

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

Write down use of laser in industry.

What is fluorescence?

Distinguished between stimulated emission and spontaneous emission.

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

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

Can electron reside inside the nucleus?

Define population inversion and metastable stable.

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

Differentiate between Line and Band spectrum.

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

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?