Advertisements
Advertisements
प्रश्न
Write the basic cause of refraction of light.
Advertisements
उत्तर
APPEARS IN
संबंधित प्रश्न
Explain how spectrum is formed.
Define refraction and state the laws of refraction.
After tracing the path of a ray of light passing through a rectangular glass slab for four different values of the angle of incidence, a student reported his observations in tabular form as given below:
| S.No | ∠ i | ∠ r | ∠ e |
| I | 30° | 19° | 29° |
| II | 40° | 28° | 40° |
| III | 50° | 36° | 50° |
| IV | 60° | 40° | 59° |
The best observation is
(A) I
(B) II
(C) III
(D) IV
A ray of light passes from water to air. How does the speed of light change?
Why is the ratio of the velocities of light of wavelengths 4000Å and 8000Å in vacuum 1: 1?
How can you bend light away from the normal?
How must light travel out of a substance if it is not going to be refracted?
An object is viewed through a glass prism with its vertex pointing upwards. It appears to be displaced upward. Explain the reason.
Fig 4.31 below shows a light ray of single colour incident normally on two prisms A and B. In each case draw the path of the ray of light as it enters and emerges out of the prism. Mark the angle wherever necessary.
Draw an í- `delta` graph for a mono chromatic raY through a glass prism of a plane and mark
(i) `delta` m, the angle of mínimum devíation
(íí) Any two values of i for which value of `delta` ís same.
Fig shows a lens as a combination of a glass block and two prisms.

(i) Name the lens formed by the combination.
(ii) what is the XX' called?
(iii) Complete the ray diagram and show the path of the incident ray PQ after passing through the lens.
(iv) The final emergent ray will either meet XX' at a point or appear to come from a point on XX'. what is the point called?
A glass slab is placed over a page on which the word VIBGYOR is printed with each letter in its corresponding colour.
- Will the image of all the letters be in the same place?
- If not, the state which letter will be raised to the maximum. Give a reason for your answer.
State the factors on which the angle of deviation depends.
Define the term refractive index of a medium in terms of velocity of light.
You are provided with a printed piece of paper. Using this paper how will you differentiate between a convex lens and a concave lens?
The diagram shows the path of a ray of light through a rectangular glass block placed in a liquid of uniform density.

Show with the help of a ray diagram the path of the ray when incident ray normally falls on the first surface of the glass block and passes through the block and the liquid.
Trace a ray of light incident at 30° on a surface if travelling from glass to air. What is the angle of refraction in this case? (R.I. for glass = 3/2).
The speed of light in air is 3 × 108 ms-1. Calculate the speed of light in water. The refractive index of water is 4/3.
