Sunday, 11 December 2011

Class 10 - Physics - Light - Numerical and Questions #eduvictors #class10-physics

Class 10 - Physics - Light - Numerical and Questions


(See also at set 1)

Q1: When an object is placed at a distance of 60 cm from a convex mirror, the magnification produced is 1/2.
Where should the object be placed to get a magnification of 1/3?

Answer:


Q2: When an object is kept at a distance of 60cm from a concave mirror, the magnification is 1/2. Where should the object be placed to get a magnification of 1/3?

Answer: (Hint: steps are the same as in the above question, except it is a concave mirror, m = -1/2. Compute f in the first case i.e. f = -20 cm and the compute u in case II i.e. u = 80 cm)

Q3(CBSE Board): A concave lens made of material of refractive index (n1) is kept in a medium of refractive index (n2). A parallel beam of light is incident on the lens. Complete the path of the rays of light emerging from a concave lens if: 
(a) n1 > n2      
(b) n1 = n2 
(c) n1 < n2

Answer:


Q4: A convex lens made of material of refractive index (n1) is kept in a medium of refractive index (n2). A parallel beam of light is incident on the lens. Complete the path of the rays of light emerging from a concave lens if:
(a) n1 > n2    
(b) n1 = n2
(c) n1 < n2
Answer:
Q5: Which of the two has great power? A lens of short focal length or a lens of large focal length?
Answer: the lens of short focal length. 
 
Q6: When a convex lens and a concave lens of equal focal lengths are placed side by side, what will be the equivalent power and the combined focal length?
Answer: Equivalent Power = 0 and Combined focal length = infinity.

Q7: When a plane mirror is rotated by an angle $\theta$, what will be the angle of rotation of the reflected ray for the fixed incident ray?

Answer: The reflected ray will be rotated twice w.r.t to the angle of rotation of the mirror. i.e. $2\theta$

Consider the following figure:

As shown, mirror M is rotated by an angle $\phi$. Let I be the incident ray, N be normal and R is the reflected ray.
Before rotation, let the incident angle be $\theta$
After rotation, normal moves by angle $\phi$,



Q8: With respect to air the refractive index of kerosene is 1.44 and that of a diamond is 2.42. Calculate the refractive index of diamond with respect to kerosene.

Answer:







23 comments:

  1. Replies
    1. it's very helpful not much helpful use correct english

      Delete
    2. Hmmm. Even u forgot to put a comma in your sentence. Use proper punctuation.😑😑😡

      Delete
    3. Need to give more. Numericals

      Delete
    4. @TanishaSharma, a sentence always starts with a capital letter.
      @HARSHVARDHANSINGHChauhan, it’s not “u” it is “you” and it’s not “even u” it’s “you even”.

      Delete
    5. @Food is Good, you have omitted a word. The word 'but' is missing between 'it's not u' and 'it is you.' Moreover you don't use speechmarks to quote words.

      Delete
    6. Thanks! For help☺️🙂👍

      Delete
    7. Thanks! For help☺️🙂👍

      Delete
  2. In Q3 the last n1<n2 should'nt be a convex lens???

    ReplyDelete
  3. Replies
    1. This comment has been removed by the author.

      Delete
  4. In Q2, u cannot be (+)80.... u has to be -ive

    ReplyDelete
    Replies
    1. this is very true but it is said that in hint apply that u is if positive so what will be the answer u should read the question nicely

      Delete
  5. Questions are too easy........post sumthing intresting

    ReplyDelete
  6. Thank you very much. Found this post very useful

    ReplyDelete
  7. thanks it is very useful for me!

    ReplyDelete
  8. It was really very helpful 😊😊.... Enough to make my concepts better and strong..Thanks a lot!!😊😊☺☺

    ReplyDelete
  9. There should be more numericals....

    ReplyDelete
  10. plzz give sough one these are so simple that should be interesting and hard s solve

    ReplyDelete
  11. it was helpful, try to give more questions, many questions were out of syllabus with regard to boards 2021, however it was easy, try to give tough ones

    ReplyDelete

We love to hear your thoughts about this post!

Note: only a member of this blog may post a comment.