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प्रश्न
Define magnifying power of a simple microscope. How can it be increased?
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उत्तर
The magnifying power of the microscope is defined as the ratio of the angle subtended by the image at the eye to the angle subtended by the object (assumed to be placed at the least distance of distinct vision D = 25 cm) at the eye, i.e.,
Magnifying power = 1 + `D/F`
Where F is the focal length of the lens.
The magnifying power of a microscope can be increased by using the lens of short focal length. But it cannot be increased indefinitely.
संबंधित प्रश्न
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.
A lens forms an erect, magnified, and virtual image of an object. Name the device which uses this principle.
If the magnification produced by a lens is - 0.5, the correct statement is ______.
The focal length of a convex lens is 25 cm. At what distance from the optical centre of the lens an object be placed to obtain a virtual image of twice the size?
The maximum magnifying power of a convex lens of focal length 5 cm can be ______.
Name the lens for which magnification can be 1. For what position of the object will the magnification be 1?
An object AB is placed between 2F1 and F1 on the principal axis of a convex lens as shown in the diagram. Copy the diagram and using three rays starting from point A, obtain the image of the object formed by the lens.
(i) Draw a ray diagram to show how the lens can be used as a ‘magnifying glass’? State the nature of the lens.
(ii) In what respect does the image in (i) above different from the image formed by a concave lens?
Write an expression for the magnifying power of a simple microscope. How can it be increased?
State two uses of magnifying glass.
