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प्रश्न
What type of lens would you use as a magnifying glass? How close must the object be to the lens?
उत्तर
For a magnifying glass, we use a convex lens. The object should be placed between the optical centre and the focus.
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संबंधित प्रश्न
Where should an object be placed in order to use a convex lens as a magnifying glass?
With the help of a labelled diagram explain how a convex lens converges a beam of parallel light rays. Mark the principal axis, optical centre, principal focus and focal length of the convex lens on the diagram.
A student did an experiment with a convex lens. He put an object at different distances 25 cm, 30 cm, 40 cm, 60 cm and 120 cm from the lens. In each case he measured the distance of the image from the lens. His results were 100 cm, 24 cm, 60 cm, 30 cm and 40 cm, respectively. Unfortunately his results are written in wrong order.
What is the focal length of this lens?
What kind of lens is used to correct
long-sightedness?
The given below figure shows an object OA and its image IB formed by a lens
. 
draw suitable rays to locate the lens and its focus.
For which position of the object does a convex lens form a virtual and erect image? Explain with the help of a ray diagram.
Why do we say that the ‘2F’ and ‘F’ points of a convex lens can be regarded as a sort of ‘turning points’ as far as the nature of the image formed by it is concerned?
Distinguish between Concave lens and Convex Lens.
Distinguish between:
Concave lens and Convex Lens
