Lakhmir Singh solutions for फिज़िक्स [इंग्रजी] इयत्ता १० आईसीएसई chapter 4 - Refraction of Light at Plane Surfaces [Latest edition]

Explain the bending of a ray of light when it travels from a rarer to a denser medium.

Explain the bending of a ray of light when it travels from a denser to a rarer medium.

Explain the bending of a ray of light when it travels from the normal to the junction of the two media.

The refractive index of diamond is 2.42. What is the meaning of this statement?

State the Snell’s laws of refraction of light.

How does the speed of light in glass change on increasing the wavelength of light?

When a ray of light enters from one medium to another having different optical densities it bends. Why does this phenomenon occur?

A ray of monochromatic light is incident from the air on a glass slab:
(i) Draw a labelled ray diagram showing the change in the path of the ray till it emerges from the glass slab.
(ii) Name the two rays that are parallel to each other.
(iii) Mark the lateral displacement in your diagram.

Write the relation between the angle of incidence and the angle of refraction for a medium.

How is the refractive index of a material related to the speed of light in it? 

What is the unit of refractive index? 

The refractive index of glass with respect to air is _aμ_g and that of water with respect to air is _aμ_w. Write the expression for the refractive index of glass with respect to water.

When a ray of light goes from air into a clear material, you see the ray bend. How much the ray bends is determined by the ______ of the material.

When light travels from a rarer to a denser medium, its speed ______.

Define the term angle of deviation.

State three factors on which the angle of deviation depends.

Draw a ray diagram to show the refraction of a monochromatic ray through a prism when it suffers minimum deviation.

A ray of light passes through an equilateral prism such that the angle of incidence is equal to the angle of emergence and each of these is equal to `3/4` of the angle of the prism. The angle of deviation is:

How does the angle of deviation produced by a prism depend on the colour of light used? Which colour of white light is deviated (i) most, (ii) least, by a prism?

A prism deviates a monochromatic ray of light through an angle d, where the angle of incidence at the surface of the prism is i. Draw a graph showing the variation of d with i. On your graph, show the angle of minimum deviation.

What do you notice when you place a beaker of water on top of a printed paper? How does the letters on the paper look like through the beaker?

Explain why the planets do not twinkle but the stars twinkle.

Jatin puts a pencil into a glass container having water and is surprised to see the pencil in a different state.

1. What change is observed in the appearance of the pencil?
2. Name the phenomenon responsible for the change.
3. Draw a ray diagram showing how the eye sees the pencil.

A fish swimming in a pond seems nearer than it really is. Explain.

How is the refractive index of a medium related to its real depth and apparent depth?

Does the depth of a tank of water appear to change or remain the same when viewed normally from above?

A glass slab is placed over a piece of paper on which VIBGYOR is printed with each letter in its corresponding colour.

1. Will the images of all the letters be in the same place?
2. The letter of which colour appears to be raised maximum and of which colour minimum? Explain your answer.

Can light be ‘piped’ like sound in a doctor’s stethoscope?

Define the term ‘critical angle’.

How is the critical angle related to the refractive index of a medium?

What is total internal reflection? 

Why upper surface of water contained in a beaker and above eye level appears silvery?

State the conditions required for total internal reflection of light to take place.

Mention one difference between reflection of light from a plane mirror and total internal reflection of light from a prism. 

Name the factors affecting the critical angle for the pair of media.

State three actions that a total reflecting prism can produce.

State whether the following statement is true or false:

Refraction occurs because light slows down in denser materials.

True or False.

The frequency of light changes during refraction.

If the angle of incidence is greater than the critical angle, light is not refracted at all, when it falls on the surface from a denser medium to a rarer medium.

The deviation produced by a prism is independent of the angle of incidence and is same for all the colours of light. 

True or False.

In total internal reflection, there is a loss of energy.

True or False.

The depth of a tank of water appears to change when viewed normally from the above.

A medium is said to be optically ______ if the speed of light slows down in it.

When a ray of light goes from air into a clear material, you see the ray bend. How much the ray bends is determined by the ______ of the material.

Light bends when it travels from water into air. We say that it is ______.

When a ray of light enters a prism, it bends ______ the normal; as it leaves the prism, it bends ______ the normal.

Total internal reflection takes place when a light ray propagates from ______ to ______ medium.

For which colour, the refractive index of glass is maximum?

The refractive indices of four media A, B, C and D are 1.44, 1.52, 1.65 and 1.36 respectively. When light travelling in air is incident in these media at equal angles, the angle of refraction will be the minimum ______.

Diamonds glitter in the dark because ______.

A ray of light is incident on a parallel-sided glass slab, as shown in the diagram. The angle of refraction for this ray of light is likely to be:

Which of the following remains constant during refraction?