Draw a labelled ray diagram to show how a ray of light is refracted when it passes:

1. From air into an optically denser medium.
2. From an optically denser medium into air.

With the help of a ray diagram, determine the position, nature and size of the image formed of an object placed at the centre of curvature of a concave mirror.

A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.

The diagrams show the appearance of a fork when placed in front of and close to two mirrors A and B, turn by turn.

1. Which mirror is convex.
2. Which mirror is concave.

Give reasons for your choice.

An object is placed at a distance of 30cm in front of a convex mirror of focal length 15cm. Write four characteristics of the image formed by the mirror.

The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should the position of the object be relative to the mirror? Draw ray diagram to justify your answer.

How will you distinguish between a plane mirror, a concave mirror and a convex mirror without touching them?

What is the position of the image when an object is placed at a distance of 20cm from a concave mirror of focal length 20cm?

A ray of light travelling in air enters obliquely into water. Does the light ray bend towards the normal or away from the normal? Why?

“The magnification produced by a spherical mirror is - 3”. List four informations you obtain from this statement about the mirror/ image.