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प्रश्न
We can burn a piece of paper by focussing the sun rays by using a particular type of lens. Name the type of lens used for the above purpose. Draw a ray diagram to support your answer.
उत्तर
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संबंधित प्रश्न
Which of the following lenses would you prefer to use while reading small letters found in a dictionary?
Study the given ray diagrams and select the correct statement from the following:
(A) Device X is a concave mirror and device Y is a convex lens, whose focal lengths are 20 cm and 25 cm respectively.
(B) Device X is a convex lens and device Y is a concave mirror, whose focal lengths are 10 cm and 25 cm respectively.
(C) Device X is a concave lens and device Y is a convex mirror, whose focal lengths are 20 cm and 25 cm respectively.
(D) Device X is a convex lens and device Y is a concave mirror, whose focal lengths are 20 cm and 25 cm respectively.
What type of lens would you use as a magnifying glass? How close must the object be to the lens?
Fill in the following blank with suitable word:
The image in a convex lens depends upon the distance of the ........... from the lens.
If the object is moved to a point only 3 cm away from the lens, what is the new position, height and nature of the image?
A lens forms an inverted image of an object. Name the kind of lens.
A teacher sets up the stand carrying a convex lens of focal length 15 cm at 42.7 cm mark on the optical bench. He asks four students A, B, C and D to suggest the position of screen on the optical bench so that a distinct image of a distant tree is obtained almost immediately on it. The positions suggested by the students were as
A. 12.7 cm
B. 29.7 cm
C. 57.7 cm
D. 72.7 cm
The correct position of the screen was suggested by
(a) A
(b) B
(c) C
(d) D
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?
In the figure given below L is a convex lens, M is a plane mirror and S is a point source of light. Rays of light from the source S return to their point of origin. Complete the ray diagram to show this. What is the point S called?
Write the name.
The lens used in simple microscope.
