English Medium Class 10 - CBSE Question Bank Solutions for Science

Fill in the following blank with suitable word: 

Light travelling along a normal is ...............refracted.

Fill in the following blank with suitable word:  

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

What is meant by 'refraction of light'? Draw a labelled ray diagram to show the refraction of light.

A ray of light travelling in air is incident on a rectangular glass block and emerges out into the air from the opposite face. Draw a labelled ray diagram to show the completer path of this ray of light. Mark the two points where the refraction of light takes place. What can you say about the final direction of ray of light?

What is meant by the 'angle of incidence' and the 'angle of refraction' for a ray of light?

Light travels more quickly through water than through glass. 

 Which is optically denser : water or glass? 

Light travels more quickly through water than through glass. 

If a ray of light passes from glass into water, which way will it bend : towards the normal or away from the normal?

When a light ray passes from air into glass, what happens to its speed? Draw a diagram to show which way the ray of light bends. 

 A coin in a glass tumbler appears to rise as the glass tumbler is slowly filled with water. Name the phenomenon responsible for this effect.

With the help of a labelled diagram, explain why a tank full of water appears less deep than it actually is. 

 Name the phenomenon due to which a pencil partly immersed in water and held obliquely appears to be bent at the water surface.

With the help of a diagram, show how when light falls obliquely on the side of a rectangular glass slab, the emergent ray is parallel to the incident ray.

 Show the lateral displacement of the ray on the diagram. 

 State two factors on which the lateral displacement of the emergent ray depends. 

Explain with the help of a labelled ray diagram, why a pencil partly immersed in water appears to be bent at the water surface. State whether the bending of pencil will increase or decrease if water is replaced by another liquid which is optically more dense than water. Give reason for your answer.

Light travelling from a denser medium to a rarer medium along a normal to the boundary:

(a) is refracted towards the normal
(b) is refracted away from the normal
(c) goes along the boundary
(d) is not refracted

When a ray of light travelling in glass enters into water obliquely:

(a) it is refracted towards the normal
(b) it is not refracted at all
(c) it goes along the normal
(d) it is refracted away from the normal

A ray of light passes from a medium X to another medium Y. No refraction of light occurs if the ray of light hits the boundary of medium Y at an angle of:

(a) 0°
(b) 45°
(c) 90°
(d) 120°

A vertical ray of light strikes the horizontal surface of some water: 

 What is the angle of incidence?

A vertical ray of light strikes the horizontal surface of some water: 

What is the angle of refraction?