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प्रश्न
Rewrite the following statement by selecting the correct option:
If a ray of light strikes a glass slab at an angle of 600 with the surface of the slab, the angle of incidence must be __________________.
विकल्प
60°
30°
40°
120°
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उत्तर
If a ray of light strikes a glass slab at an angle of 600 with the surface of the slab, the angle of incidence must be 30°.
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संबंधित प्रश्न
Explain how spectrum is formed.
What is a spectrum?
Write a short note on dispersion of light.
Select from the following the best experimental setup for tracing the path of a ray of light passing through a rectangular glass slab.
(a) P
(b) Q
(c) R
(d) S
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
Explain the term absolute refractive index of a medium and write an expression to relate it with the speed of light in vacuum.
Why is the ratio of the velocities of light of wavelengths 4000Å and 8000Å in vacuum 1: 1?
Write the relation between the angle of incidence and the angle of refraction for a medium.
Draw diagrams to show the refraction of light from glass to air. In diagram, label the incident ray, refracted ray, the angle of incidence (i) 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?
When a lighted candle is held in front of a thick plane glass mirror, several images can be seen, but the second image is the brightest, give reason.
How does the angle of deviation produced by a prism change with increase in the angle of incidence. Draw a curve showing the variation in the angle of deviation with the angle of incidence at a prism surface.
The diagram alongside shows the refraction of a ray of light from air to a liquid.
- Write the values of (i) angle of incidence, (ii) angle of refraction.
- Use Snell’s law to find the refractive index of liquid with respect to air.
In fig 4.18, name the ray which represents the correct path of light while emerging out through a glass block.
Fill in the blanks to complete the following sentence
When light travels from a denser to a rarer medium, its speed ……………….
An object is viewed through a glass prism with its vertex pointing upwards. It appears to be displaced upward. Explain the reason.
A Water pond appears to be 2.7 m deep. If the refractive index of water is 4/3, find the actual depth of the pond.
While performing the experiment on tracing the path of a ray of light through a rectangular glass slab, in which of the following experimental set-ups is a student likely to get best results? P1 and P2 are the positions of pins fixed by him.
(A) I
(B) II
(C) III
(D) IV
Four students A, B, C and D traced the paths of incident ray and the emergent ray by fixing pins P and Q for incident ray and pins R and S for emergent ray for a ray of light passing through a glass slab.
The correct emergent ray was traced by the student:
(1) A
(2) B
(3) C
(4) D
-
- the angle of refraction and
- the angle of deviation for the ray?
Fill in the blank to complete the following sentence:
When light travels from a rarer to a denser medium, it bends ...........
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 line XX' called?
(iii) Complete the path of the incident ray PQ after passing through the lens.
(iv) The final emergent ray either meets XX' at a point or appears to come from a point on XX'. Label it as F, What is this point called?
The refractive index of air with respect to glass is defined: as gµa = sin i/sin r
Write down a similar expression for aµg in terms of angle i and r.
In the diagram below, PQ is a ray of light incident on a rectangular glass block.
How are the angles ‘i’ and ‘e’ related to each other?
Draw ray of light bending towards the normal while passing from air to glass. Label your diagrams.
Draw ray of light bending towards the normal while passing from glass to water. Label your diagrams.
After a robbery, if a window has been broken, there will be tiny particles of glass. Some of these will be found at the scene of the crime and some may be caught in the thief’s clothing. If the police can prove that these particles are identical, they have a strong case.
A method of doing this is to suspend the particles of glass in a special liquid. Light of a single colour is thrown through the liquid and the particles viewed through a microscope. The temperature of the liquid is then slowly altered. This alters the speed of light through the liquid (i.e., it alters the refractive index). At one particular temperature, the particles of glass disappear. It this happens at the same temperature for both sets of glass particles, they probably came from the same broken pane of glass.
Complete and copy the diagram to show how light bends when it travels from the liquid to the glass and back to the liquid, If the light slows down in the glass.
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What should be the rate of the speed of light through the liquid to the speed through the glass so that there is no refraction of light at the boundaries of the glass block when the system is illuminated by the light of one colour?
Explain with the help of a diagram of how fish is able to see the objects above it.
A ray of light is incident at an angle of 45° on one face of a rectangular glass slab of thickness 10 cm and refractive index 3/2. Calculate the lateral shift produced ______.
Draw the ray diagram of a glass slab having medium A and B for the velocity of light ray VA and VB respectively and define Snell's law.
- If VB = 1.5 VA, then which medium is denser?
- What is the refractive index of A with respect to B?
- What is the refractive index of B with respect to A?
Observe the figure and name the ray AB, ray CD, ray GH.
Which colour of white light travels fastest in any medium except air?
