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High School/JEE/NEET/IPhO Physics | 17-19 Yrs

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  1.  
  2. Sir, we have done all these for paraxial rays but what if these rays were marginal?
    5 months ago by Nitish Kumar Yadav

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  3.  
  4. How can I see solutions of questionsat
    1 years ago by physicsgalaxy

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  5.  
  6. how the angle alpha is equal to critical angle
    2 years ago by Kailash

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  7.  
  8. R 3 |= R 4 c T | 0 |\| 0 |= |_ | G |-| T
    3 years ago by

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  9.  
  10. sir aapne variable refractive index to phdhaya nhi nhi refraction of light , plzz reply sir as soon as possible becz sir aapka reply matters a lot.....
    3 years ago by Priya Khradia

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  11.  
  12. how can I increase the video speed??
    3 years ago by Sohan Dash

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  13.  
  14. Why is the refractive index of medium of the refracted ray 1 sir? Should'nt it be 4/3?
    3 years ago by

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  15.  
  16. sir from where can i get the solutions of que. sets
    4 years ago by

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  17.  
  18. I am a big fan. I really appreciate the efforts and hard work that you put into while making these lectures. Thank You, sir.
    4 years ago by Aniruddha Mukherjee

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  19.  
  20. Sir I got it .thanks for this awesome explaination .
    5 years ago by prahas ranjan

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  21.  
  22. Sir as RI of all the slabs are different then the extent of bending of light in all the slabs will be different.Then how can be the final refracted light will be parallel to initial light Ray ?
    5 years ago by prahas ranjan

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  23.  
  24. Here in this ques why we have not multiplied 1.5 with 15/2.5 as the light from the object will enter from the medium of refractive index 2.5 to medium of RF. 1.5
    5 years ago by simran kamboj

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  25.  
  26. sir, is this formula applicable to any width of object or only to object of small width ?
    5 years ago by Abhishek Mania

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  27.  
  28. What is the purpose if refraction of light?
    5 years ago by DHRUV KUMAR
    Ans 1 ->
    Refraction is basically used for determining the bending ability of a ray. Also used in solar appliances
    5 years ago by DHRUV KUMAR
    Ans 2 ->
    Refraction is basically used for determining the bending ability of a ray. Also used in solar appliances
    5 years ago by DHRUV KUMAR
    Ans 3 ->
    Refraction is basically used for determining the bending ability of a ray. Also used in solar appliances
    5 years ago by DHRUV KUMAR

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  29.  
  30. sir , qusets 1 k question no 15 ka solution bta dejiye...
    5 years ago by MOHIT SINGH

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  31.  
  32. a man standing on the edge of a swimming pool looks at a stone lying on the bottom. the depth of the swimming pool equal to h. At what distance from the surface of water is the image of the stone formed if the line of vision makes an angle theta with the normal to the surface.
    5 years ago by vishesh jindal

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  33.  
  34. sir in questions ko phle khud banaye ya phir pahle discussion ka weight kare
    5 years ago by ashutoshpal

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  35.  
  36. Sir in the note, Shouldn't there be object instead of observer as we didn't change the distance of observer from the slab?
    5 years ago by Vaasu Bisht

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  37.  
  38. Sir, what if A=2c ? That gives us zero deviation. Will any light ray pass through the prism?
    5 years ago by Santhosh Prabahar

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  39.  
  40. Sir, how did you get the formula for magnification of the image produced by refraction of light?
    5 years ago by Santhosh Prabahar

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  41.  
  42. Sir, why did you say that the emerging angle is equal to the incident angle?
    5 years ago by Santhosh Prabahar

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  43.  
  44. Sir in the note, Shouldn't there be object instead of observer as we didn't change the distance of observer from the slab
    5 years ago by Yash Pratap

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  45.  
  46. Dear Sir, Am i correct that if starting media and ending media of light is same then the emergent ray will be parallel to last refracted ray?
    6 years ago by Somnath Panda
    Ans 1 ->
    yes
    5 years ago by N P GDattatreya
    Ans 2 ->
    yes
    5 years ago by Santhosh Prabahar

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  47.  
  48. Dear sir, 1.In lecture 6 solution, the inner refracting angles(which you have denoted by theta) as equal.But here the inner refracting angles i.e r1 and r2 are not equal?? why is that so 2.In lecture 4 you have used Snell's law for the whole path of light but here you have divided the Snell's law for two different surfaces which have different constants? Why is that
    6 years ago by Somnath Panda

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  49.  
  50. sir from where we get the value of u
    6 years ago by

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  51.  
  52. SIR I HAVE A QUESTION IF WE HAVE A SMALL PARTICLE OSCILLATIING ALONG THE PRINCIPLE AXIS OF A THIN CONVEX LENS ,HAVING AMPLITUDE (A), WILL IT LOOK LIKE OSCILLATING IN PHASE OR OUT OF THE PHASE IN THE IMAGE ??????
    6 years ago by TAMAJIT BANERJEE

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  53.  
  54. please explain why you equated x/u=21-x
    6 years ago by anita singh

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  55.  
  56. Sir, how did u get this formula : d=A(u-1)
    6 years ago by Pratyush Ranjan Roul

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  57.  
  58. As mentioned in log magnification on reflection, Object point closer to mirror its image point was created father from mirror Will that same apply in refraction?
    6 years ago by MUKUL GUPTA

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  59.  
  60. A BEAM OF PARALLEL RAYS OF DIAMETER 'b' PROPAGATES IN GLASS AT AN ANGLE THETA TO ITS PLANE.FIND DIAMETER OF THE BEAM WHEN IT TO AIR THROUGH THIS FACE
    6 years ago by Arunachalam B J

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  61.  
  62. in that qs.where a concave mirror was filled with liquid we were asked to find the object dist. such that it's image had to be coinciding with object why can't we shift the concave mirror to it's appt. ht. as seen from above and equate h+d/(ri)=2f ........where ri =ref.index?
    7 years ago by Sudarshana Ghosh

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  63.  
  64. sir can i solve it by dividing opt.dist. by vel(in slab)? if so then opt.distance is refr.idex x 1 ?
    7 years ago by Sudarshana Ghosh

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  65.  
  66. Why can't i solve by 4(1-1/1.33)?
    7 years ago by Sudarshana Ghosh

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  67.  
  68. A container of depth H is filled with two immiscible transparent liquids of refractive indices u1 and u2, and respectively. The depth of each type of liquid is H/2 .when viewed from above, the apparent depth of the vessel is
    7 years ago by Rajesh lamba

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  69.  
  70. Which colour of light travels with minimum velocity in Glass..?
    7 years ago by Sivaprasad S
    Ans 1 ->
    speed of light in glass is = c/µ and µ depends upon wavelength according to cauchy's relation which we have already studied... now whichever wavelengths are available in any light beam for the lowest wavelength µ will be maximum and its speed will be minimum in glass...
    7 years ago by Physics Galaxy

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  71.  
  72. Sir please tell me how to get it that when u get a real image then u will always get it at the other side?
    7 years ago by Sudarshana Ghosh
    Ans 1 ->
    Sir, how did you get the formula for magnification of the image produced by refraction of light?
    5 years ago by Santhosh Prabahar

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  73.  
  74. sir then for this question refractive index of glass is not required?
    7 years ago by abhishek
    Ans 1 ->
    refractive index of glass is required to check if 45 degrees is greater than the critical angle or not.
    7 years ago by shabbir chatrissa

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  75.  
  76. Sir will the light ray pass from the base surface of the prism after total internal reflection from the second mat surface of the prism if A is greater than twice the critical angle?
    8 years ago by Yash Selot

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  77.  
  78. Quset2 Q13 kaise solve karu
    8 years ago by Faizan Ali Saiyed

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  79.  
  80. Sir is it independent of the distance of the OBJECT from the glass slab or the OBSERVER ???
    8 years ago by Udayaditya Singh
    Ans 1 ->
    Yes the magnitude of shift is independent of it.
    8 years ago by Rishank Pandey
    Ans 2 ->
    Sir in the note, Shouldn't there be object instead of observer as we didn't change the distance of observer from the slab
    5 years ago by Yash Pratap

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  81.  
  82. we have to do experiment of Refraction of light ray using red blue & green torch in a evacuated room.Sir what will be observation?
    8 years ago by TUSHAR SINHA
    Ans 1 ->
    deflection of light rays of diferent colours
    5 years ago by N P GDattatreya
    Ans 2 ->
    deflection of light rays of diferent colours
    5 years ago by N P GDattatreya

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  83.  
  84. why does the light ray in denser medium ray gets reflected but in rarer medium it gets refracted? I mean is there any explanation for above phenomenon ( like based on equations)or is it experimentally observed ?
    8 years ago by Bharath Ram
    Ans 1 ->
    When light is going from denser to rarer medium, angle of refraction can be given by sin^-1(denser/rarer), which will at some point will go out of domain of sin inverse function. Hence no refraction occurs at that point and internal reflection starts.
    6 years ago by Prajjwal Pandey

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  85.  
  86. Sir isn't the value of Sin theta 3/4. There happens to be a mistake.
    8 years ago by ashwin sudarshan
    Ans 1 ->
    Sorry. realized i was wrong
    8 years ago by ashwin sudarshan

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  87.  
  88. The correct exposure time for a photographic print is 20sec at a distance of 2feet from a 40candela lamp. The exposure time for the same print at a distance of 4 feet from a 20candela lamp is
    8 years ago by Vishesh Gupta

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  89.  
  90. Dear sir how can you say that light will incident normally to the river??.?
    8 years ago by Abinay gangireddygari
    Ans 1 ->
    agskjagdmgskagdkhasgkjdgskagdkjsgkg
    8 years ago by Vishesh Gupta
    Ans 2 ->
    sun rises at the horizon .so the light enters the lake at grazing incidence
    6 years ago by Sakthi Vel

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  91.  
  92. Sir in the second refraction the angle of incidence is r1 but u have taken sin(i-r2) but we must take sin(r1-r2) in delta 2 expression...
    8 years ago by Abinay gangireddygari
    Ans 1 ->
    this is becoz we r taking the lateral displacement in the direction of initial incident ray bt not the refracted ray......so on watching carefully everything will be clear automatically....
    8 years ago by Khushboo Jain

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  93.  
  94. Sir, a ray of light is incident normally on one face of a prism of angle 30 degree and refractive index v2. the angle of deviation will be?
    9 years ago by lakshya singhal
    Ans 1 ->
    On one face if light incident normally, it incident on the second inner face of prism at angle of incidence 30° where you can use snells law and calculate emergence angle then deviation angle will be e-30°
    9 years ago by Physics Galaxy

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  95.  
  96. Sir.,will the path of light differ if the sphere is hollow and solid.
    9 years ago by R Yashwanth
    Ans 1 ->
    above case is of solid sphere... if it is hollow the light will not be deviated as thin walls of sphere behave as glass plate and will not offer any deviation to light ray..
    9 years ago by Physics Galaxy

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  97.  
  98. How do you know that the angles are small ?? please explain ??
    9 years ago by Karthikesh
    Ans 1 ->
    Pl read the question carefully...It is mentioned in the question...
    9 years ago by Physics Galaxy

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  99.  
  100. a cubical vessel with opaque walls,is so placed that the eye of an observer cannot see its buttom but can see the enire wall.
    9 years ago by abhishek sinha
    Ans 1 ->
    a cubical vessel with opaque walls,is so placed that the eye of an observer cannot see its buttom but can see the enire wall.asmall object is placed at the buttom from 10cm from one corner.what minimum depth of water should be poured into the vessel which enable the observer to see the object?(refractive index=4/3)
    9 years ago by abhishek sinha
    Ans 2 ->
    In this case we need to limit the refractive index of liquid such that the light ray from corner of bottom which goes to the top surface at opposite corner at critical angle (45°) then bottom will not be seen but eye must be place along the line joining the diagonal of the vessel. If eye is placed normally above the vessel bottom will always be seen...
    9 years ago by Physics Galaxy

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  101.  
  102. a fish under water observes a freely falling stone in air.if the refractive index of water is 4/3,what is the apparent acceleration of the stone as observed by the fish?
    9 years ago by abhishek sinha
    Ans 1 ->
    You can watch modules - 25 to 29 under section 'Optics' of the topic 'Refraction of Light' to understand it...In the que stated by you the apparent acceleration of the stone will be refractive index times the actual acceleration i.e. (4/3)g...
    9 years ago by Physics Galaxy

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  103.  
  104. Why frequency of light wave does not changes when it undergoes refraction?
    9 years ago by Kartike Bansal
    Ans 1 ->
    Change in frequency during refraction will change the energy of wave in general which cannot happen under ideal conditions so it cannot happen... So under real conditions also it cannot happen for all type of waves including electromagnetic and mechanical waves...
    9 years ago by Physics Galaxy

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  105.  
  106. sir would you derive the refraction formula..??
    9 years ago by rohith vaddavalli
    Ans 1 ->
    Pl refer download section for this...
    9 years ago by Physics Galaxy

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