Explain with the help of a diagram, why the convex lens is also called a converging lens.

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?

A doctor has prescribed a corrective lens of power +1.5 D. Find the focal length of the lens. Is the prescribed lens diverging or converging?

An object 1cm tall is placed 30cm in front of a convex mirror of focal length 20cm. Find the size and position of the image formed by the convex mirror.

What is meant by ‘refraction of light’? Draw a labelled ray diagram to show the refraction of light.

If the magnification of a body of size 1m is 2, what is the size of the image?

If two lenses (convex) are in contact with each other, what happens to the ray after refraction?

Draw a ray diagram to show the formation of a real diminished 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.

A concave mirror and a convex lens are held separately in water. What changes, if any, do you expect in the focal length of either?

What is the minimum number of rays required for locating the image formed by a concave mirror for an object. Draw a ray diagram to show the formation of a virtual image by a concave mirror.