What is a lens? Distinguish between a convex lens and a concave lens. Which of the two is a converging lens : convex lens or concave lens?

At what distance from a concave mirror of focal length 10cm should an object 2cm long be placed in order to get an erect image 6cm tall?

Describe an activity to show that the colours of white light splinted by a glass prism can be recombined to get white light by another identical glass prism. AIso draw ray diagram to show the recombination of the spectrum of white light.

A shop security mirror 5.0m from certain items displayed in the shop produces one-tenth magnification.

1. What is the type of mirror?
2. What is the radius of curvature of the mirror?

You are provided with two lenses of focal length 20cm and 30cm, respectively. Which lens will you use to obtain more convergent light?

An object is placed at a distance equal to 2f in front of a convex lens. Draw a labelled ray diagram to show the formation of image. State two characteristics of the image formed.

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.

A small object is so placed in front of a convex lens of 5cm focal length that a virtual image is formed at a distance of 25cm. Find the magnification

An object is placed at a distance of 100cm from each of the above lenses A and Calculate:

1. Image distance, and
2. Magnification, in each of the two cases.

A concave lens has focal length 15cm. At what distance should the object from the lens be placed so that it forms an image at 10cm from the lens? Also find the magnification produced by the lens.