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प्रश्न
An object is placed at a distance 2f from a convex lens of focal length f. The size of the image formed is ______ that of the object.
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उत्तर
An object is placed at a distance 2f from a convex lens of focal length f. The size of the image formed is equal to that of the object.
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संबंधित प्रश्न
A converging lens forms the image of an object placed in front of it beyond 2F2 of the lens. Where is the object placed?
Draw a ray diagram to show how a converging lens can form a real and enlarged image of an object.
Draw a ray diagram to show how a converging lens can form an image of the sun. Hence give a reason for the term ‘burning glass’ for a converging lens used in this manner.
An object is placed at a distance 5 cm from a convex lens of focal length 10 cm. The image formed is virtual, upright and _____.
Which of the following lens would you prefer to use while reading small letters found in a dictionary?
An object is placed at a distance 20cm from a convex lens of focal length 10cm. Find the image distance and nature of the image.
An object of height 3cm is placed at 10cm from a concave lens of focal length 15cm. Find the size of the image.
Sudha finds out that the sharp image of the window pane of her science laboratory is formed at a distance of 15 cm from the lens. She now tries to focus the building visible to her outside the window instead of the window pane without disturbing the lens. In which direction will she move the screen to obtain a sharp image of the building? What is the approximate focal length of this lens?
Draw ray diagrams showing the image formation by a convex lens when an object is placed
- between optical centre and focus of the lens
- between focus and twice the focal length of the lens
- at twice the focal length of the lens
- at infinity
- at the focus of the lens
Complete the following table based on image formation by convex lens:
| Position of Object | Position of Image | Nature of Image |
| At infinity | (a) ______ | Real and inverted and highly diminished image |
| Beyond 2F1 | (b) ______ | (c) ______ |
| At 2F1 | (d) ______ | Real, inverted, same size (as object) image |
| Between F1 and 2F1 | Beyond 2F2 | (e) ______ |
| At focus F1 | (f) ______ | Real, inverted and highly enlarged image |
