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प्रश्न
Observe the following figure and answer the questions.
a) Which optical instrument shows arrangement of lenses as shown in the figure?
b) Write in brief the working of this optical instrument.
c) How can we get different magnifications in this optical instrument?
d) Draw the figure again and labelled it properly
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उत्तर
a) Arrangement of lenses shown in the figure is refracting telescope.
b) 1) object lens collect the light coming form the distant object and forms the image
2)The image works as object for the eye piece which forms the final image.
c) We can get different magnifications by using the eye piece with different focal lengths.
d)
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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.
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.
A 1 cm high object is placed at a distance of 2f from a convex lens. What is the height of the image formed?
For what position of an object a real, diminished image is formed by a convex lens?
Fill in the following blank with suitable word:
Parallel rays of light are refracted by a convex lens to a point called the ........
Fill in the following blank with suitable word:
The image in a convex lens depends upon the distance of the ........... from the lens.
An object is placed at a distance equal to 2f in front of a convex lens. Draw a labelled ray diagram to show the formation of image. State two characteristics of the image formed.
State whether convex lens has a real focus or a virtual focus.
A convex lens produces an inverted image magnified three times of an object placed at a distance of 15 cm from it. Calculate focal length of the lens.
An object 3 cm high is placed 24 cm away from a convex lens of focal length 8 cm. Find by calculations, the position, height and nature of the image.
What type of lens is used to correct
hypermetropia
In figure , name the ray which represents the correct path of light while emerging out through
a glass block.
Define the term principal axis of a lens.
The focal length of a thin convex lens is ______ than that of a thick convex lens.
Answer the following question.
List four precautions which a student should observe while determining the focal length of a given convex lens by obtaining an image of a distant object on a screen.
State the nature and position of the object on the principal axis to obtain a real image of the same size
Find the odd one out and give its explanation.
Which of the following statements is true?
Distinguish between Concave lens and Convex lens.
