Draw a ray diagram to show the formation of a virtual magnified image of an object by a convex lens. In your diagram, the position of object and image with respect to the principal focus should be shown clearly.

The lens A produces a magnification of, -0.6 whereas lens B produces a magnification of +0.6:

1. What is the nature of lens A?
2. What is the nature of lens B?

Where would the image be formed by a convex mirror if the object is placed:

1. Between infinity and pole of the mirror?
2. At infinity?

Draw labelled ray-diagrams to show the formation of image in both the cases.

Explain why, a real image can be projected on a screen but a virtual image cannot.

What is meant by power of a lens? What does its sign (+ve or -ve) indicate? State its S.I. unit. How is this unit related to focal length of a lens?

Briefly describe how you would find the focal length of a concave mirror quickly but approximately.

What is meant by:
Draw diagram to show the action of convex mirror on a beam of parallel light rays. Mark on this diagram principal axis, focus F, centre of curvature C, pole P and focal length ƒ, of the convex mirror.

A 5cm tall object is placed perpendicular to the principal axis of a convex lens of focal length 18cm at a distance of 12cm from it. Use lens formula to determine the position, size and nature to the image formed.