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प्रश्न
Simple microscope : Number of convex lens one : : compound microscope : _______
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उत्तर
Simple microscope : Number of convex lens one : : compound microscope : Number of convex lenses two
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संबंधित प्रश्न
An object 5 cm is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position, nature and size of the image.
An object AB is placed between O and F1 on the principal axis of a converging lens as shown in the diagram.
Copy the diagram and by using three standard rays starting from point A, obtain an image of the object AB.
A 1 cm high object is placed at a distance of 2f from a convex lens. What is the height of the image formed?
If an object is at a considerable distance (or infinity) in front of a convex lens, where is the image formed?
Define principal axis, principal focus and focal length of a convex lens.
How could you find the focal length of a convex lens rapidly but approximately?
Name one simple optical instrument in which the above arrangement of convex lens is used.
A convex lens of focal length 8 cm forms a real image of the same size as the object. The distance between object and its image will be:
(a) 8 cm
(b) 16 cm
(c) 24 cm
(d) 32 cm
A convex lens of focal length 15 cm produces a magnification of +4. The object is placed:
(a) at a distance of 15 cm
(b) between 15 cm and 30 cm
(c) at less than 15 cm
(d) beyond 30 cm
A parallel oblique beam of light falls on a convex lens. Draw a diagram to show the refraction of light through the lens.
A lens forms an upright and magnified image of an object State whether the image is real or virtual
In the following cases, where must an object be placed in front of a convex lens so that the image formed is upright and enlarged?
To find the image distance for varying object distances in case of a convex lens of focal length 15 cm, a student obtains on a screen a sharp image of a bright object by placing it at 20 cm distance from the lens. After that he gradually moves the object away from the lens and each time focuses the image on the screen.
(a) In which direction-towards or away from the lens does he move the screen to focus the object?
(b) How does the size of image change?
(c) Approximately at what distance does he obtain the image of magnification –1?
(d) How does the intensity of image change as the object moves farther and farther away from the lens?
The image obtained while finding the focal length of convex lens is ....................
What is the difference between a double convex and a bi-convex lens?
What happens to the image formed by a convex lens if its lower part is blackened?
_______ times larger images can be obtained by using a simple microscope.
: Object near the lens : : ______ : 
