Question
What are lenses? Describe the positions and nature of the images produced due to the different positions of the object.
Answer
| Position of object | Position of image | Nature of image |
| (i) Infinity | At f2 | Real and inverted |
| (ii) Beyond C | Between f2 and 2f2 | Real and inverted |
| (iii) At C | At 2f2 | Real and inverted |
| (iv) Between C and F | Beyond 2f2 | Real and inverted |
| (v) At F | At infinity | Real and inverted |
| (vi) Between P and F | Same side of the object | Virtual and erect |
For concave lens
| Position of object | Position of image | Nature of image |
| (i) Infinity | At f1 | Virtual and erect |
| (ii) infinity and the optical centre | Between f1 and the optical centre | Virtual and erect |
