ICS Part 2 Physics Chapter 19 Short Questions Preparation

Question # 1

Can a pair production take place in vacuum?Explain

Ans 1: No,pair production can not take place in vacuum.
In order to conserve the momentum and energy,their presence of heavy nucleus is essential,The vacuum has no particle or heavy nucleus,Therefore pair production can not take place in vacuum.

Question # 2

As a solid is heated and begins to glow ,why does it first of its absolute.

Ans 1: Since the red light has longest wavelength ,so it will be emitted first and solid appears red first.

Question # 3

Define ionization potential and excitation potential.

Ans 1: Ionization potential:The potential necessary to remove an electron from the atom is called ionization potential,It is expressed in volts.
Ans 2: Excitation potential:The potential require to raise orbital electron in atom from one energy level to an other is called excitation potential.

Question # 4

Define Stopping potential and Threshold frequency.

Ans 1: Stopping potential:The stopping potential is the potential difference applied to stop the electrons from being ejected from the surface when the light fall on it.
Threshold frequency:The minimum of frequency of incident light at which electrons are emitted from a surface is called threshold frequency.

Question # 5

What do you understand by work function and stopping potential?

Ans 1: The minimum amount energy required to remove an electron from the surface of a metal is called work function.
And the stopping potential is the potential difference applied to stop the electrons from being ejected from the surface when the light falls on it.

Question # 6

Does the dilation mean that time really passes more slowly in moving system or that it only seems to pass more slowly.Explain briefly.

Ans 1: According to dilation formula
t= $\scriptstyle {\sqrt {1-{\frac {v^{2}}{c^{2}}}}}$ "
This relation show that a clock moving with respect to an observe appears to move slow then it does when it is at rest with respecttohim.So the moving clocks just appears to run slowly to the observer at rest.Hence time dilation is an apparent change and it only seems to pass more slowly but not actually.

Question # 7

Write at least two justification for light to behave as wave and as a particle.

Ans 1: Interference and diffraction confirms wave nature of light while photoelectric effect and compton effect confirms particle nature of light.

Question # 8

A satellite is orbiting around earth.Is its frame of reference inertial or non-inertial ?Justify your answer.

Ans 1: The motion of the satellite is synchronized with the earth so it is in the same frame of reference in which earth lies.Hence the frame of reference will be inertial.

Question # 9

Photoelectric effect give the evidence of the particle nature of light,Explain it how?

Ans 1: If light were simple a wave like phenomena ,then increasing the intensity and thereby increasing the total energy failing on the surface would be expected to eventually provide enough energy to release electron no matter what the frequency .Furthermore in the classical picture one would expect the maximum energy of the emitted electrons to depend on the intensity of light--but it does not.So this is evidence that light behaves as if it were a particle.

Question # 10

What are advantages of NAVSTAR navigation system?

Ans 1: NAVSTAR is used to locate the position and find the speed of an object anywhere on Earth up to to an accuracy of 2 cms^-1.

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ICS Part 2 Physics Chapter 19 Short Questions Preparation

12th Class PhysicsShort Questions Preparation

12th Class Physics Chapter Wise Preparation

Online Short Questions For Chapter 8 "ICS Part 2 Physics Chapter 19 Short Questions Preparation "

Physics - ICS Part 2 Physics Chapter 19 Short Questions Preparation

Can a pair production take place in vacuum?Explain

As a solid is heated and begins to glow ,why does it first of its absolute.

Define ionization potential and excitation potential.

Define Stopping potential and Threshold frequency.

What do you understand by work function and stopping potential?

Does the dilation mean that time really passes more slowly in moving system or that it only seems to pass more slowly.Explain briefly.

Write at least two justification for light to behave as wave and as a particle.

A satellite is orbiting around earth.Is its frame of reference inertial or non-inertial ?Justify your answer.

Photoelectric effect give the evidence of the particle nature of light,Explain it how?

What are advantages of NAVSTAR navigation system?

Prepare Complete Set Wise Questions For Chapter 8 "ICS Part 2 Physics Chapter 19 Short Questions Preparation "

Set 1

Set 2

Set 3

ICS Part 2 Physics Chapter 19 Short Questions Preparation - Set 1

Can a pair production take place in vacuum?Explain

As a solid is heated and begins to glow ,why does it first of its absolute.

Define ionization potential and excitation potential.

Define Stopping potential and Threshold frequency.

What do you understand by work function and stopping potential?

Does the dilation mean that time really passes more slowly in moving system or that it only seems to pass more slowly.Explain briefly.

Write at least two justification for light to behave as wave and as a particle.

A satellite is orbiting around earth.Is its frame of reference inertial or non-inertial ?Justify your answer.

Photoelectric effect give the evidence of the particle nature of light,Explain it how?

What are advantages of NAVSTAR navigation system?

ICS Part 2 Physics Chapter 19 Short Questions Preparation - Set 2

Define pair production and annihilation of matter.

Differentiate between inertial and non-inertial frame of reference.

Will higher frequency of light ejects greater number of electrons than low frequency of light?

What do you know by annihilation of matter?

What are conclusion made from the pair production?

Why don't we observe a Compton Effect with visible light?

Define work function and threshold frequency.

The rest mass of photon is zero.Is its momentum also zero?

If you are moving in a spaceship at very high speed relative to the earth.Would you notice difference(a)In your pulse rate(b)In the pulse rate of people on the earth?

Give two postulate of special theory of relativity.

ICS Part 2 Physics Chapter 19 Short Questions Preparation - Set 3

If you are moving in a spaceship at very high speed relative to the earth.Would you notice difference(a)In your pulse rate(b)In the pulse rate of people on the earth?

As a solid is heated and begins to glow ,why does it first of its absolute.

Distinguished between photoelectric effect and Compton effect.

Will the bright light ejects more from metal surface than dimmer light of tha same colour?

Which has the lower energy quanta,radio waves or x rays?Explain

What are advantages of NAVSTAR navigation system?

Differentiate between special theory of relativity and general theory of relativity.

What are black body radiations and how can you get a black body?

Why can red light be used in a photographic dark room when developing films,but a blue or white light can not?

Define Stopping potential and Threshold frequency.

ICS Part 2 Physics Chapter 19 Short Questions Preparation

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