Advertisements
Advertisements
प्रश्न
Which of the following lens would you prefer to use while reading small letters found in a dictionary?
विकल्प
A convex lens of focal length 5 cm
A concave lens of focal length 5 cm
A convex lens of focal length 10 cm
A concave lens of focal length 10 cm
Advertisements
उत्तर
A convex lens of focal length 5 cm
APPEARS IN
संबंधित प्रश्न
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.
A lens forms an inverted image of an object. What is the nature of the image real or virtual?
An object is placed at a distance of more than 40 cm from a convex lens of focal length 20 cm. The image formed is real, inverted and ______.
Where should an object be placed so that a real and inverted image of the same size is obtained by a convex lens?
A small bulb is placed at the principal focus of a convex lens. When the bulb is switched on, the lens will produce
Explain the rules for obtaining images formed by a convex lens with the help of ray diagram.
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.
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 |
