An object 4 cm in height, is placed at 15 cm in front of a concave mirror of focal length 10 cm. At what distance from the mirror should a screen be placed to obtain a sharp image of the object. Calculate the height of the image.

An object is placed between infinity and the pole of a convex mirror. Draw a ray diagram and also state the position, the relative size and the nature of the image formed.

An object placed on a metre scale at 8 cm mark was focussed on a white screen placed at 92 cm mark, using a converging lens placed on the scale at 50 cm mark.

1. Find the focal length of the converging lens.
2. Find the position of the image formed if the object is shifted towards the lens at a position of 29.0 cm.
3. State the nature of the image formed if the object is further shifted towards the lens.

The magnification of an image formed by a lens is –1. If the distance between the object and its image is 60cm, what is the distance of the object from the optical centre of the lens? Find the nature and focal length of the lens. If the object is displaced 20cm towards the optical centre of the lens, where would the image be formed and what would be its nature? Draw a ray diagram to justify your answer.

A combination of lenses for a camera contains two converging lenses of focal lengths 20cm and 40cm and a diverging lens of focal length 50cm. Find the power and focal length of the combination.

Two lenses have power of

1. +2D
2. –4D

What is the nature and focal length of each lens?

Describe with the help of a ray-diagram, the formation of image of a finite object placed in front of a convex lens between f and 2f Give two characteristics of the image so formed.

Describe with the help of a ray diagram the nature, size and position of the image formed when an object is placed in front of a convex lens between focus and optical centre. State three characteristics of the image formed.

The shiny outer surface of a hollow sphere of aluminium of radius 50cm is to be used as a mirror:

1. What will be the focal length of this mirror?
2. Which type of spherical mirror will it provide?
3. State whether this spherical mirror will diverge or converge light rays.

A student wants to project the image of a candle flame on a screen 48 cm in front of a mirror by keeping the flame at a distance of 12 cm from its pole.

1. Suggest the type of mirror he should use.
2. Find the linear magnification of the image produced.
3. How far is the image from its object?
4. Draw ray diagram to show the image formation in this case.