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Question
What is a magnifying glass (or a simple microscope)? Draw a ray diagram to show how a convex lens may be used as a magnifying glass. Where should the object be placed? State three characteristics of the image formed.
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Solution
A magnifying glass is a convex (or converging) lens of B short focal length mounted in a plastic or wooden frame provided with a handle. It is used to see small objects or to read small letters.

The ray diagram showing the use of a convex lens as a magnifying glass is given in the figure.
The object should be placed in front of the lens between its optical centre and focus.
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The following diagram shows an object AB and a converging lens L with foci F1 and F2. Draw two rays from the object AB and complete the diagram to locate the position of the image CD. Also mark on the diagram the position of eye from where the image can be viewed.

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State two uses of magnifying glass.
