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प्रश्न
Observe the given figure and answer the following questions.
- Where is the above type of lens construction used?
- What type of image is formed by an objective lens?
- What happens instead of placing at Fo if the object is placed in between O and Fo?
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उत्तर
- The above type of lens construction is used in a compound microscope.
- The image formed by the objective is real, inverted, and formed at a distance within the focal length of the eyepiece.
- If the object is placed in between O and Fo, a virtual image will be formed on the same side of the objective as that of the object. As a result, compound microscope will not be able to operate as expected.
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संबंधित प्रश्न
To find the image-distance for varying object-distances in case of a convex lens, a student obtains on a screen a sharp image of a bright object placed very far from the lens. After that he gradually moves the object towards the lens and each time focuses its image of the screen.
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(c) What happen when he moves the object very close to the lens?
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Rewrite the image distances in the correct order.
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The focal lengths of four convex lenses P, Q, R and S are 20 cm, 15 cm, 5 cm and 10 cm, respectively. The lens having greatest power is :
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hypermetropia
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Study the diagram below.
what are the points O, O’ called?
The given below figure shows an object OA and its image IB formed by a lens.
A convex lens forms an image of an object equal to the size of the object. State two more characteristics of the image.
Out of the five incident rays shown in the figure find the three rays that are obeying the laws of refraction and may be used for locating the position of image formed by a convex lens:
(A) 1, 2 and 3
(B) 2, 3 and 4
(C) 3, 4 and 5
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(a) What type of a lens can be used as a magnifying glass?
(b) Show by a ray diagram the formation of a real image by simple magnifying lens.
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Define the principal focus of a convex lens.
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- What is the kind of lens shown in the above figure?
- If a real inverted image is to be formed by this lens at a distance of 7m from the optical centre, then show with calculation where should the object be placed.
- Draw a neatly labelled diagram of the image formation mentioned in (ii).
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