Wave Optics Questions and Answers

In Young s double slit experiment the slits are 2 mm apart and are illuminated by photons of two wavelengths 12000 A and 10000 A At what minimum distance from the common central bright fringe on the screen 2m from the slit will a bright fringe from one interference pattern coincide with a bright fringe from the other NEET 2013 1 6 mm 2 4 mm 3 3 mm 4 8 mm

Two slits in Youngs experiment have widths in he ratio 1 25 The ratio of intensity at the maxima and minima in the interference pattern max is L 1 3 9 121 2 4 9 4 min Re AIPMT 2015 49

Two Polaroids P and P are placed with their axis perpendicular to each other Unpolarised light is incident on P A third polaroid P3 is kept in between P and P such that its axis makes an angle 45 with that of P The intensity of transmitted light through P2 is NEET 2017 1 3 2 2 4 10 4 lo

The interference pattern is obtained with two coherent light sources of intensity ratio n In the interference pattern the ratio 1 3 n n 1 max min Imax min NEET Phase 2 2016 n n 1 2 4 2 n 1 2 n n 1 will be

A parallel monochromatic beam of light is incident normally on a narrow slit A diffraction pattern is formed on a screen placed perpendicular to the direction of the incident beam At the first minimum of the diffraction pattern the phase difference between the rays coming from the two edges of the slit is 1998 A O C T B 2 D 2

What is Malus law The principal planes of two Nicol prisms form an angle of 30 Prove that the intensity of the transmitted light diminished in the ratio of 3 2 if the angle between principal planes becomes 45

Q4 a What will be the highest order spectra which may be seen with light of wavelength 5500A by means of a grating with 4000 lines cm the affect on diffraction attorn dua to Fraunhofer diffesation b Explain beig

Question ID 20412 Two light waves from two coherent sources of intensity ratio 25 1 produce interference What is the ratio of the maxima and minima formed in the interference pattern Options 25 1 Option ID 105616 5 4 Option ID 105617 9 4 Option ID 105618 26 24 Option ID 105619 Option IR 105616

In a YDSE distance between the slits is 2 mm the distance of the screen from the slits is 1 m and the wavelength of light used is 5000 The fringe width is x 10 mm Answer 00 01 02 03 04 05 06 07 08 09 00 01 02 03 04 05 06 07

A Young s double slit experiment is performed using light of wavelength X 5000 which emerges in phase from two slits a distance d 3 x 10 7 m apart A transparent sheet of thickness t 1 5 10 7 m is placed over one of the slits The refractive index of the material of this sheet is fl

In standard Young s double slit experiment using two wavelength of light A 5000 and A 5500 the nth bright fringe of one wavelength coincides with n 1 th dark fringe of other wavelength Find the value of n

In a standard YDSE set up d 1 0 mm D 1 m Now if one of the slits is covered with a transparent sheet of refractive index 1 4 the shift in the fringe pattern is found to be shift by 4 mm The thickness of the sheet is 4 m O 10 km

In a double slit experiment when light of wavelength 400 nm was used the angular width of the first minima formed on a screen placed 1m away was found to be 0 2 What will be the angular width of the first minima if the entire experimental apparatus is immersed in water water 4 3 3 0 05 1 0 266 2 0 15 4 0 1 WO0188

If the two slits in Young s double slit experiment are o unequal width then O The bright fringes will have unequal spacing The bright fringes will have unequal brightness O The fringes do not appear The dark fringes are not perfectly dark

A clear sheet of polaroid is placed on the top of similar sheet so that their axes make an angle sin with 5 each other The ratio of intensity of the emergent light to that of unpolarised incident light is O 16 25 09 25 4 5

A compound microscope has a magnification of 30 The focal length of eyepiece is 5 cm The magnification produced by objective lens if the final image is formed at least distance of distinct vision 25 cm is 6 05 07

What will be the height of image of an object of height 2 mm placed on the axis of convex mirror of radius of curvature 40 cm at a distance of 20 cm from convex mirror 20 mm 10 mm 6 mm hr min 1 mm

A point object O is placed in front of glass rod having spherical end of radius of curvature 30 cm The image would be formed at g 1 5 Glass Air 04 15 cm p 30 R At infinity C O 30 cm to left of P O 1 cm to right of P O 18 cm to left of P

Two identical thin plano concave lenses u 1 5 each having radius of curvature 30 cm are placed in contact with common axis as shown in the figure If the intervening space is filled with oil of refractive index 1 8 the focal length of the combination is 50 cm 50 cm 25 cm 25 cm

In a standard YDSE set up the intensity of the central maximum is lo The intensity at a point where the path difference between the light from the two slits is 4 wavelength of light used will be 04 0 O O 11 12 O 210

If the two slits in Young s double slit experiment are of unequal width then The bright fringes will have unequal spacing The bright fringes will have unequal brightness The fringes do not appear O The dark fringes are not perfectly dark

10 Light of wave length 600 nm is incident on a single slit The first minimum of the diffraction pattern is obtained at a distance of 4mm from the centre The distance between the screen and the slit is 2m What is the width of the slit 26 3mm 1 0 1mm 3 0 5m 4 0 6 mm

In Young s interference experiment two slits are illuminated with orange light of wavelength 6000 A The interference pattern is observed on screen far from slit planes If the central bright fringe is numbered as zero what must be path difference for light from two slits at fourth bright fringe 1 3 m 3 24 um 2 1 6 m 4 3 6 m

ray of light falls on the surface of a spherical glass paper weight making an angle w the normal and is refracted in the medium at an angle B The angle of deviation of the emerge ray from the direction of the incident ray is 1 2 2 B 3 B 2 4

A single slit is illuminated by light composed of two wavelength A1 and X2 One observes that due to Fraunhofer diffraction the first minimum obtained for A1 coincides with the second diffraction minimum of A2 What will be the relation between A1 and 2

7 Light takes t sec to travel a distance x cm in vacuum and takes t sec to travel 10x cm in a medium The critical angle corresponding to the media is 1 sin 3 sin 10t t 10t 1 2 sin 4 sin t 10t 10t

A particle of mass m is constrained to move on the surface of a sphere of radius R The sphere is resting on ground a Set up the Lagrangian for the particle by clearly identifying the kinetic energy and potential energy b What are the constants of the motion for the particle

Example 9 When light of wavelength 5000A in vacuum travels through same thickness in glass and water the difference in the number of waves is 400 Find thickness Refractive indices of glass and water 3 4 are and respectively 2 3

Light initially in air air 1 is incident at angle 01 64 on the surface of water Deter 1 33 The light passes through the water of thickness t 5 cm and strikes the water glass interface at a distance d from the initial normal The glass has an index of refraction nga 1 5 1 5 points Calculate the angle of refraction 02 at the air water interface 82 2 5 points Calculate the angle of incidence 83 at the water glass interface 03 at the end of the assessment 3 15 points Find the value of the distance d d cm 4 5 points At the water glass interface the light will undergo 5 Air Water Glass

10 points A beam of light travels trough water and hits a glass surface The angle between the incident beam and the normal to the glass surface is 0 39 The index of refraction of water is 1 33 and the index of refraction of this type of glass is 1 65 a 5 points What is the angle of refraction 0 0 b 5 points What is the critical angle of this interface 0 0

2 Three waves Y 2Asin wt 3 Y 2Asin wt in cot and y3 Asin t interfere 3 each other The amplitude of the resultant wave is NCERT Pg 377 1 A 3 2A 2 Zero 4 3A

The stars sometimes appears brighter and at some other time fainter This is because ucha au ff 3 4 STRUT Of atmosphere refraction Of scattering of light of The stars are the point sources of light art er af

Two coils have mutual inductance 0 01 H The current in the first coil change accordin g to equation 1 10 sin2wt where 10 5 A and w 5 0 rad s Then the magnitude of induced e m f in secondary coil due to mutual inductance at t 4 Ons is

Diffraction pattern of a single slit consists of central band which is a wider brighter and accompanied with alternate dark and bright bands of decreasing intensity b narrow bright and alternate dark and bright bands of equal intensity c wider bright and alternate dark and bright bands of equal intensity d dark with alternate dark and bright hands of equal intensity

A slit of width 1 2 x 104 cm is illuminated by a monochromatic light of wavelength 6000 A Calculate the half angular width of central bright maximum in its Fraunhofer diffraction pattern a 40 b 60 c 30 d 50

45 The shape of the fringes observed in interference is O Circular Hyperbolic Save Next Save Back Skip Questi BPH2101 PHYSICS REMAINING TIME HOURS MINUTES SECONDS 1 Ostraight Elliptical

Two periodic waves of intensities I and I pass through a region at the same time in the same direction Th sum of the maximum and minimum intensities is AIPMT 2008 1 1 1 2 1 1 3 1 1 4 2 1 1

36 The theory of wave particle duality states that all matter has properties of Oboth a particle and a wave Oeither a particle of a wave BPH2101 PHYSICS REMAINING TIME HOURS MINUTES SECONDS 1 48 27 Ojust a wave and not a particle Ojust a particle and not a wave

37 Each source produce intensity I at P The phase difference between resultant intensity at point P is Sot S S S S S 0 P

In Young s double slit experiment a light source consist of two wavelength 5200 and 6000 is used Find the distance of 4th bright fringe from the central maxima for 5200 Given that the distance between the slits is 2 mm and the distance between plane of slits and the screen is 200 cm a 5 11 x 10 6 b 2 08 x 10 c 3 09 x 104 d 512 x 105

33 For the two parallel rays AB and DE shown here BD is the wavefront For what value of wavelength of rays destructive interference takes place between ray DE and reflected ray CD A 3x B 2x D F E B 60 Mirror C x D 2x

When a light wave travels from denser to rarer medium its P velocity decreases R wavelength increases Q frequency remains unchanged A P and R are correct B Q and R are correct C P and Q are correct D all are cor

Two slits and 2 on the x axis and symmetric with respect to y axis are illuminated by a parallel monochromatic light beam of wavelength as shown in figure The distance between the slits is d Point O is the midpoint of the line S S and this point is considered as the origin The slits are in horizontal plane The interference pattern is observed on a horizontal plate acting as screen of mass m which is attached to one end of a vertical spring of spring constant k The other end of the spring is fixed to the ground At t 0 the plate is at a distance D d below the plane of the slits S S and spring is in its natural length The plate is left from rest from its initial position Assume that the spring is light and plate always remains horizontal unde a 2 a Ref Ych 4H1 A2 Ychauffu y r Y GRI falda di 12 fa fa ya fa 24 Ha vllai i Ra fav com cufaru Rin Audich kan Ych Geafer R on ych f u 4 Chrka Gia SI USI GERI ARTERI 0 1 S 1314 Ruch Rafa farihicken R 31 Augeh 14 wc u u fau zga A B GR Xg d X Question The rate at which fringe width is changing when plate crosses through its mean position of oscillation is hw kufa gurdi da Prvi Xg D Rafald m k S m k di elele m

A double split experiment is performed with light of wave length 500 nm A thin film of thickness 2um and refractive index 1 5 is introduced in the path of the upper beam The location of the centrs maximum will A Remain un shifted B Shift downward by nearly two fringes C Shift upward by nearly two fringes D Shift downward by 10 fringes

Ho n n transparent slabs are arranged one on top of each other The refractive indices of the material of the slabs are H1 H Hz and the thicknesses are t t2 t3 tn An image is formed at a particular position when a point object is seen perpendicularly through this combination of slabs If the image is formed at the same position when seen through a single glass slab instead of the combination of slabs what is the equivalent refractive index of the new glass slab n ti i 1 n t

Three polaroids p1 p2 and p3 are kept such that P1 and p3 are crossed and if the angle between the pass axes of p2and p is 37 and the intensity of unpolarized light incident on piis lo then the intensity of light coming out of p3will be nearly P

1 1 m s 3 1 5 m 2 In YDSE with two identical slits when upper slit 8 is covered with a transparent sheet of mica second order minima is observed above the centre of the screen and second order maxima below it Which of the following can not be possible value of phase difference caused by the mica sheet 1 3 T 3 2 2 m s 4 2 5 m 10 3 2 4 11t 3 1 12 3 1 5 YDSE 2 227 4 2 5 g feat sen vie fer fra Reat en fra fer A ANAIA HIS vir 3 WIN 10 3 g 7x 11x 3

In the Young s double slit experiment the intensity of light at a point on the screen where the path difference is is K being the wave length of light used The intensity at a point where the path difference is 4 will be Question Type Single Correct Type 1 K 2 K 4 3 K 2

13 Unpolarized light of equal intensity is incident on four pairs of polarizing filters Rank in order from largest to smallest the intensities I to I transmitted through the second polarizer of each pair a b c pass axis d 60 pass axis pass axis 30 pass axis 30 30 pass 30 0 8 axis A a b c d C b c a d pass axis 30 30 60 pass axis pass axis B d a b c D a b c d All India Open Test leader Test Series Joint Package Coursel

is incident on a glass slab 1 54 in a direction as shown in figure The reflected ray OB is pass through a Nicol prism On viewing through a Nicole prism we find on rotating the prism that A 33 O N 33 B 1 The intensity is reduced down to zero and remains zero 2 The intensity is reduced down some what and rises again 3 There is no change in intensity 4 The intensity gradually reduces to zero and then again increases