Advertisements
Advertisements
प्रश्न
Observe the figure and name the ray AB, ray CD, ray GH.
Advertisements
उत्तर
- Ray AB - Incident ray
- Ray CD - Refracted ray
- Ray GH - Emergent ray
APPEARS IN
संबंधित प्रश्न
Explain how spectrum is formed.
When rays of light are incident on a glass slab then the incident ray and emergent ray are _________ each other.
- perpendicular
- parallel
- opposite
- concurrent
Choose the correct alternative and rewrite the following sentence.
A ray of light strikes the glass slab at an angle of 50°. What is the angle of incidence?
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
Four students P, Q, R and S traced the path of a ray of light passing through a glass slab for an angle of incidence 40° and measured the angle of refraction. The values as measured them were 18°; 22°; 25° and 30° respectively. The student who has performed the experiment methodically is
(A) P
(B) Q
(C) R
(D) S
On the basis of the experiment, "To trace the path of a ray of light through a rectangular glass slab", students of a class arrived at which one of the following conclusions?
(A) Angle of incidence is greater than the angle of emergence.
(B) Angle of emergence is smaller than the angle of refraction.
(C) Emergent ray is parallel to the refracted ray.
(D) Incident ray and emergent ray are parallel to each other.
Explain the term absolute refractive index of a medium and write an expression to relate it with the speed of light in vacuum.
Draw a ray diagram to show the refraction of a monochromatic ray through a prism when it suffers minimum deviation
Draw the diagram of refraction of light in the glass slab
Why is the ratio of the velocities of light of wavelengths 4000Å and 8000Å in vacuum 1: 1?
A ray of light passes from glass into air. The angle of refraction will be:
(a) equal to the angle of incidence
(b) greater than the angle of incidence
(c) smaller than the angle of incidence
(d) 45°
How can you bend light away from the normal?
Draw diagrams to show the refraction of light from
- air to glass, and
- glass to air. In each diagram, label the incident ray, refracted ray, the angle of incidence
- and the angle of refraction (r).
Light of a single colour is passed through a liquid having a piece of glass suspended in it. On changing the temperature of liquid, at a particular temperature the glass piece is not seen. When is the glass piece not seen?
What do you understand by the statement the refractive index of glass is 1.5 for white light?
The critical angle for glass-air is 45° for the light of yellow colour. State whether it will be less than, equal to, or more than 45° for (i) ref light, (ii) blue light?
The refractive index of glass is 1.5. From a point P inside a glass block, draw rays PA, PB and PC incident on the glass air surface at an angle of incidence 30°, 42° and 60° respectively.
- In the diagram show the approximate direction of these rays as they emerge out of the block.
- What is the angle of refraction for the ray PB?
`("Take" sin 42° =2/3)`
A ray of light enters a glass slab ABDC as shown in figure and strikes at the centre O of the circular part AC of the slab. The critical angle of glass is 42°. Complete the path of the ray till it emerges out from the slab. Mark the angles in the diagram wherever necessary.
A total reflecting right angled isosceles prism can be used to deviate a ray of light through:
(a) 30° (b) 60° (c) 75° (d) 90°.
Select from the following the best experimental set-up for tracing the path of a ray of light through a glass slab:
(A) I
(B) II
(C) III
(D) IV
Draw a diagram to show the splitting of white light into its constituent colours.
Fig. shows a ray of white light that passes through a prism and produces a spectrum.
(a) Name the phenomenon that is taking place.
(b) What colour would you see at X and Y?
(c) What radiation would you detect above X and below Y?
Draw a ray diagram showing the lateral displacement of a ray of light when it passes through a parallel sided glass slab.
Name the phenomenon responsible in the following case:
Apparent bending of a stick in water
Name the phenomenon responsible in the following case:
Twinkling of stars
Why upper surface of water contained in a beaker and above eye level appears silvery?
Name one main factor on which the direction of bending of a ray of light depends.
During sunset and sunrise, the sun is seen when it is slightly below the horizon. Give reason.
What is the refractive index of vacuum
Comment on the statement ‘The refractive index of glass is 3/2.’
In what condition a prism is said to be in the position of minimum deviation? What is the direction of the refracted ray inside the prism in this condition?
Draw ray of light bending towards the normal while passing from glass to water. Label your diagrams.
Draw a diagram of a prism and label:
(i) the base,
(ii) the refracting surfaces,
(iii) the refracting edge,
(iv) the refracting angle in it.
