A 3 cm tall object is placed 18 cm in front of a concave mirror of focal length 12 cm. At what distance from the mirror should a screen be placed to see a sharp image of the object on the screen. Also calculate the height 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.

How far should an object be placed from a convex lens of focal length 20 cm to obtain its image at a distance of 30 cm from the lens? What will be the height of the image if the object is 6 cm tall?

What would your image look like if you stood dose to a large:

1. Convex mirror?
2. Concave mirror?

Give reasons for your answer.

An object 4cm high is placed at a distance of 10cm from a convex lens of focal length 20cm. Find the position, nature and size of the image.

With the help of a diagram, explain why the image of an object viewed through a concave lens appears smaller and closer than the object.

An object placed 20cm in front of a mirror is found to have an image 15cm.

1. In front of it,
2. Behind the mirror.

Find the focal length of the mirror and the kind of mirror in each case.

A man standing in front of a special mirror finds his image having a very small head, a fat body and legs of normal size. What is the shape of:

1. Top part of the mirror?
2. Middle part of the mirror?
3. Bottom part of the mirror?

Give reasons for your choice.

When an object is placed 10cm in front of lens A, the image is real, inverted, magnified and formed at a great distance. When the same object is placed 10cm in front of lens B, the image formed is real, inverted and same size as the object:

1. What is the focal length of lens A?
2. What is the focal length of lens B?
3. What is the nature of lens A?
4. What is the nature of lens B?

Which type of lens is:

1. A converging lens, and which is.
2. A diverging lens? Explain your answer with diagrams.