Short-sightedness is corrected by using a:

Where must an object be placed in front of a converging lens for the image to be virtual, erect and magnified? Name one use of this arrangement.

A diverging lens has a focal length of 20 cm. Find its power.

State two differences between the image formed by a converging lens and that formed by a diverging lens for a real object.

An object is placed 20 cm from a converging lens of focal length 15 cm. Find the position, nature and magnification of the image.

Find the power of a converging lens of focal length 25 cm.

A person cannot see distant objects clearly. Name the defect, the lens used to correct it, and explain why that lens works.