Ques 1 : i)Two different parts of monochromatic light act as coherent sources. ii) Two different monochromatic sources act as coherent sources. iii) Two.

Ques 1 :

i)Two different parts of monochromatic light act as coherent sources.

ii) Two different monochromatic sources act as coherent sources.

iii) Two different part of same wave front act as coherent sources

iv) Two images of same source act as coherent sources

a) i) & ii

c) iii) & iv)

b) ii) & iii)

d) ii) & iv)

Ans 1: c) iii) Two different part of same wave iii) Two different part of same wave front act as coherent sourcesfront act as coherent sourcesiv) Two images of same source act iv) Two images of same source act as coherent sources as coherent sources

Ques 2 :

Pairs of sources of light that can act as coherent sources are

a) Two images of same source

c) Two different parts of same wave front

b) One source and its image

d) All of the above

Ans -2: d) All of the above

Ques 3 :

In interference

a) Energy is created at Maxima.

d) Energy is redistributed by movement of the medium from minima to maxima

b) Energy is destroyed at minima.

c) Energy is redistributed from minima to maxima without the movement of medium from minima to maxima .

Ans 3: c) Energy is redistributed from minima Energy is redistributed from minima to maxima without the movement to maxima without the movement of medium from minima to maxima of medium from minima to maxima

Ques 4 :

When two coherent sources of light interfere

a) Maxima is obtained where phase difference is odd multiple of π

c) Minima is obtained where phase difference is even multiple of π

b) Maxima is obtained where phase difference is even multiple of π

d) None of the above

Ans 4:

b) Maxima is obtained where phase difference is even multiple of π

Ques 5 :

In Huygens's Double slit experiment the valid equation at minima is

a) Path difference = (2n-1)λ/2

c) Path difference = (2n-1)λ

b) Path difference = (2n+1)λ/2

d) Path difference = (2n+1)λ

Ans 5 :

a) Path difference = (2n-1)λ/2

Ques 6 :

Intensities of successive maximas due to diffraction from single slit are in the ratio of

a) 1: 1/22: 1/64 : 1/122 …..

c) 1: 22 : 64 : 122 …..

b) 1 : 1 : 1: ……

d) 1 : 2 : 4 : 8 ………

Ans 6 :

a) 1: 1/22: 1/64 : 1/122 …..

Ques 7 :

Diffraction is the phenomenon of bending of light

a) While passing from one medium to another

c) From sharp edges into geometric image

b) From sharp edges into geometric shadow.

d) From sharp edges into geometric image or shadow.

Ans 7:

d) From sharp edges into geometric image or shadow.

Ques 8 :

In diffraction from N no of parallel slits there are …….. Secondary minima and …….. Secondary maxima between two successive principal maxima

a) N+1, N+2

c) N-1 , N-2

b) N, N-1

d) N-2, N-1

Ans 8:

c) N-1 , N-2

Ques. 9 :

Maximum order n of spectrum that can be observed with diffraction grating of grating element (a+b) is given by

a) n ≤ λ (a + b)

c) n ≥ λ /(a + b)

b) n ≤ λ /(a + b)

d) n ≤ (a + b) / λ

Ans 9:

d) n ≤ (a + b) / λ

Ques. 10 :

Hazarduous effect of laser is the most on

a) Skin

c) Heart

b) Eyes

d) Blood

b) Eyes

Ans 10:

Ques 11 :

If widths of transparency and opacity are equal then missing order of spectra are

a) 2, 4, 6, 8 …………..

c) 3, 6, 9, ………………..

b) 1, 5, 9, 13 ….

d) 1, 3 , 5 , 7,

Ans 11:

a) 2, 4, 6, 8 …………..

Ques 12 :

For two objects to be just resolved first minima of one should fall on central maxima of other. This statement was given by

a) Einstein.

c) Rayleigh.

b) Michelson and Morley.

d) Newton

Ans 12:

c) Rayleigh.

Ques 13 What would the mass of a 9.11 X 1010-31-31 kg electron be if it were to travel at c? 

a) Infinite

c) 1.6 x 10-12 Kg

b) 9.11 x 10-31 Kg

d) Zero

Ans 13:

a) Infinity

Ques 14: An observer on a spacecraft moving directly away from the sun is moving at a speed of 0.3 c will find that the light waves pass by him (from behind) at a relative speed of .

a) 1.3 c

c) 0.7 c

b) c

d) 0.9c

Ans 14:

b) c

Ques 15: Which experiment was the first compelling evidence in favour of time dilation?

d) Young's double-slit

c) Rutherford's Alpha Scattering

b) The Michelson-Morley interferometer

a) Muon decay

Ans 15 :

a) Muon decay

Ques 16:

Evidence for conversion of mass into energy and vice versa are

a) Nuclear reactor and pair production

c) Hydrogen bomb and atom bomb

b) Pair production and Nuclear reactors.

d) Energy from Sun and Stars

Ans16 :

a) Nuclear reactor and pair production

Ques 17 :

Kinetic Energy of a relativistic particle is twice its rest mass energy.

a) Moving mass is two times its rest mass

c) Moving mass is three times the rest mass

b) Moving mass is half of its rest mass.

d) Moving and rest mass are always same.

Ans 17:

c) Moving mass is three times the rest mass

Ques 18 :

What is the minimum no of energy levels needed for lasing?

a) 1

c) 2

b) 4

d) 3

Ans 18:

d) 3

Ques 19 : When electrons drops down from a higher energy state and recombine with hole what is produced?

a) Gamma ray.

c) Photon.

b) Phonon.

d) Current.

Ans 19 :

c) Photon.

Ques 20 : What particle play major role in the process of lasing.

a)Neutron

c) Electron.

b) Proton.

d) Krypton.

c) Electron.c) Electron.

Ans 20 :

Ques 21: Basic difference between three and four level laser is that

a) Four level is independent of pumping rate

b) Three level is independent of pumping rate

c) Four level is independent of pumping power

d) Three level is independent of pumping power

a) Four level is independent of pumping rate a) Four level is independent of pumping rate

Ans 21 :

Ques 22: If a wave can be polarised it must be:

a) Electromagnetic Wave

b) Longitudinal Wave

c) Seismic wave

d) Transverse wave

d) Transverse waved) Transverse wave

Ans 22 :

Question 23Question 23

The relation between Brewster angle λ and critical angle C is

a) (sin C) -1 = tan λb) Sin C = tan λc) C = λd) C = 1/ λ

Ans. 23Ans. 23

a) (sin C) -1 = tan λ

Ques. 24Ques. 24

The wave fronts of Ordinary and Extra-ordinary The wave fronts of Ordinary and Extra-ordinary waves in a crystal are shown in figure. The crystal is waves in a crystal are shown in figure. The crystal is a) –ve crystal a) –ve crystal b) +ve crystal b) +ve crystal c) Neutralc) Neutral

Ans. 24Ans. 24

b) +ve crystalb) +ve crystal

Ques. 25Ques. 25

The wave fronts of Ordinary and Extra-ordinary The wave fronts of Ordinary and Extra-ordinary waves in a crystal are shown in figure. waves in a crystal are shown in figure. a)a)Spherial wave front is for O-raySpherial wave front is for O-rayb)b)Elliptical wave front is for O-rayElliptical wave front is for O-rayc)c) Spherial wave front is for E-raySpherial wave front is for E-rayd)d)Straight line is for E-rayStraight line is for E-ray

Ans. 25Ans. 25

a)a) Spherial wave front is for O-raySpherial wave front is for O-ray

Ques. 26Ques. 26

a)a)Only statement 1 is correct.Only statement 1 is correct.b)b)Only statement 2 is correct Only statement 2 is correct c)c) Both the statements 1 & 2 are Both the statements 1 & 2 are correctcorrectd)d)Statement 1 is correct but statement Statement 1 is correct but statement 2 is not correct2 is not correct

Read Following Statements

1. Optic axis is a line equally inclined to all edges meeting at blunt corners and any line parallel to it is also an optic axis.

2. Velocities of O-ray and E-ray are same in along optic axis

Ans. 26Ans. 26

c) Both the statements 1 & 2 are correctBoth the statements 1 & 2 are correct

Ques. 27Ques. 27

a)a) statement 1 is correct.statement 1 is correct.b)b) statement 2 is correct statement 2 is correct c)c) Both the statements 1 & 2 are Both the statements 1 & 2 are correctcorrectd)d) None of the above statement are None of the above statement are correct correct

1. Elliptically polarised light is produced when O-ray and E-ray having equal amplitude superimpose over each other and have a path difference of /4

2. Circularly polarised light is produced when O-ray and E-ray having equal amplitude superimpose over each other and have a path difference of /4

Ans. 27Ans. 27

b) Statement 2 is correctb) Statement 2 is correct

Ques. 28Ques. 28

Nicol Prism Nicol Prism

a)a)Acts as Polariser and can be used to Acts as Polariser and can be used to produce only plane polarised light.produce only plane polarised light.

b)b)Acts as Polariser and produces only Acts as Polariser and produces only circulary polarised light.circulary polarised light.

c)c)Acts as only analyser and produces plane Acts as only analyser and produces plane polarised light.polarised light.

d)d) Can act both as polariser and analyser.Can act both as polariser and analyser.

Ans. 28Ans. 28

d) Can act both as polariser and Can act both as polariser and analyser.analyser.

Ques. 29Ques. 29

a)a) i) and ii) are correct.i) and ii) are correct.b)b) ii) and iii) are correct ii) and iii) are correct c)c) iii) and iv) are correctiii) and iv) are correctd)d) i) and iv) are correcti) and iv) are correct

You send a traveling wave along a particular string by oscillating the string. On increasing the frequency of oscillation

i) The Speed of wave increases

ii) Wavelength of wave decreases without any change of speed

If instead of increasing frequency tension in string is increased

iii) Speed of wave decreases

iv) Wave length of wave increases

d)d) i) i) The Speed of wave increases and and iv) iv) Wave length of wave increases

are correctare correct

Ans. 29Ans. 29

Ques. 30Ques. 30

a)a)Optical Path and Geometric path are Optical Path and Geometric path are always same.always same.

b)b)Geometric path is always larger than Geometric path is always larger than optical path. optical path.

c)c) Geometric path is always less than Geometric path is always less than optical path.optical path.

d)d) Geometric path is always larger than Geometric path is always larger than optical path in Transparent medium.optical path in Transparent medium.

Ans. 30Ans. 30

d)d) Geometric path is always larger than optical Geometric path is always larger than optical path in Transparent medium.path in Transparent medium.

Ques. 31Ques. 31According to Einstein postulates of theory of relativityAccording to Einstein postulates of theory of relativityi)i) Laws of physical phenomenon are same in all Non inertial Laws of physical phenomenon are same in all Non inertial

frames of referenceframes of referenceii)ii) Velocity of light is independent of motion of source and Velocity of light is independent of motion of source and

observerobserveriii)iii) Laws of physical phenomenon are same in all inertial Laws of physical phenomenon are same in all inertial

frames of referenceframes of referenceiv)iv) Velocity of light is independent of motion of source but Velocity of light is independent of motion of source but

depends upon motion of observerdepends upon motion of observera)a) ii) and iii) are correct.ii) and iii) are correct.b)b) i) and ii) are correct.i) and ii) are correct.c)c) i) and iv) are correct.i) and iv) are correct.d)d) ii) and iv are correct.ii) and iv are correct.

Ans. 31Ans. 31

a)a) ii) Velocity of light is independent of ii) Velocity of light is independent of motion of source and observermotion of source and observer and and iii) Laws of physical phenomenon are iii) Laws of physical phenomenon are same in all inertial frames of same in all inertial frames of referencereference

are correct.are correct.

Ques. 32Ques. 32

a)a)In diffraction all fringes are of unequal In diffraction all fringes are of unequal width and in interference all fringes are width and in interference all fringes are of equal width.of equal width.

b)b)In diffraction all fringes are of equal In diffraction all fringes are of equal width and in interference all fringes are width and in interference all fringes are of unequal width.of unequal width.

c)c) In diffraction as well interference In diffraction as well interference intensities of all fringes are equal. intensities of all fringes are equal.

d)d)Diffraction and refraction both show that Diffraction and refraction both show that light is transverse in naturelight is transverse in nature

Ans. 32Ans. 32

a)a) In diffraction all fringes are of In diffraction all fringes are of unequal width and in interference unequal width and in interference all fringes are of equal width.all fringes are of equal width.

Ques. 33Ques. 33

If n is the order of spectrum and N is Resolving If n is the order of spectrum and N is Resolving power of grating is given bypower of grating is given by

• N / nN / n• N x nN x n• n / N n / N d)d)x dx d

Ans. 33Ans. 33

b) N x nb) N x n

Ques. 34Ques. 34

In relativistic Mechanics energy E and momentum In relativistic Mechanics energy E and momentum p are related by equationp are related by equation

• EE22 = p = p22 c c2 2 + m+ moo22 c c44

• EE22 = p = p22 c c22 + mo + mo22 c c22

• E = pE = p22/2m/2md)d)p = (2mE)p = (2mE)1/21/2

Ans. 34Ans. 34

a)a) EE22 = p = p22 c c2 2 + mo+ mo22 c c44

Ques. 35Ques. 35If a thin transparent sheet of refractive index m is If a thin transparent sheet of refractive index m is

introduced in the path of one of the interfering introduced in the path of one of the interfering beams the shift in the fringes is given by beams the shift in the fringes is given by

a)

D

td )1(

b)

d

tD )1(

c)

td

D

)1(

Ans. 35Ans. 35

a) D

td )1(