(1) Light travelling from air to water will always change direction.

(4) A pencil dipped in water appears bent in the middle because of refraction.

(5) The value of μ, for a particular colour of light is constant.

(6) The geometric centre of a curved mirror is its focus.

(7) A convex mirror is also called the divergent mirror.

(8) Rays from a bulb placed at focus of a concave mirror is reflected as parallel rays.

(9) A convex mirror can be conveniently used as shaving mirror.

(10) Convex mirrors are divergent because they have low focal length.

(2) Physical density and optical density are the same thing.

(3) Speed of only violet light is reduced when passing through a glass slab.

(1) If a ray passes from air to glass without deviation, it must be ____________ to the surface of glass.

(2) The angle of incidence is formed between the incident ray and ____________.

(3) Splitting of sunlight into its component colours is ____________.

(4) Glass is optically ____________ than air.

(6) A ray of light passing through ____________ in a concave mirror retraces its path.

(7) A real image will always be ____________.

(8) Focal length of a convex mirror is half of the ____________.

(9) If an image is formed behind the mirror it must be ____________.

(10) The mirror used as street light reflectors are ____________.

(5) By convention in a ray diagram the dotted lines are used for ____________.

(3) What are angle of incidence and angle of refraction?

(7) State two properties of a real image.

(8) Explain conjugate foci with the help of an example.

9. Explain conjugate foci with the help of an example.

10. What are the properties of a virtual image?

(2) What is refraction of light?

(6) What is a convergent lens?

(9) What are the properties of a virtual image?

(10) Why convex mirrors are preferred over plane mirrors as rear-view mirrors in vehicles?

(1) How can we calculate refractive index of a medium?

(4) Draw a ray diagram, showing how a swimming pool appears shallower than it is?

(5) What is a mirage?

1. Define the following: 

a) Centre of curvature of a curved mirror. 

b) Focal length of a concave mirror. 

c) Principal axis of a curved mirror

2. How can we calculate refractive index of a medium?

3. What is refraction of light?

4. What are angle of incidence and angle of refraction?

5. Draw a ray diagram, showing how a swimming pool appears shallower than it is?

6. What is a mirage?

7. What is a convergent lens?

8. State two properties of a real image.

(2) Why do we see the Sun, even after it has actually set beyond the horizon?

(1) Why do the stars twinkle at night while the planets do not ?

(3) Explain dispersion of white light through a prism with the help of a diagram.

(4) Explain how speed of light helps us to calculate refractive index of a medium?

(5) In making ray diagrams, which are the standard rules we must follow?

(6) In the study of reflection through curved mirror, what are convenient rays?

(7) What is meant by focus and focal length of a concave mirror; explain with the help of a diagram.

(8) How can we differentiate between concave and convex mirrors?

(9) What are the differences between an image formed by a plane mirror and a concave mirror with object at infinity?

(10) Why convex mirrors are preferred over plane mirrors as rear-view mirrors in vehicles?

Meeting of at least two reflected ray from the mirror

It can obtained on a screen.

Its optical density must be high.

Stars behave as point source of light that undergoes refraction through layers of the air.

Meeting of at least two reflected ray from the mirror

As a rear-view mirror in a car

1.55

Speed of the component lights have different speed in glass.

Light is travelling from denser medium to rarer medium.

Distance between the pole and the focus is called focal length.

The image formed is inverted and highly diminished.