1. What is meant by a lens? How many curved surfaces are there in a lens? (AS1) 1 Mark
2. Which lens is used in a microscope? (AS6) 1 Mark
3.
What does the above figure show? (AS4) 1 Mark
4.
What does the above figure show? (AS5) 1 Mark
5.
What does the above figure show? (AS5) 1 Mark
6.
What does the above figure show? (AS5) 1 Mark
7.
Complete the figure and find out the nature of the image. (AS5) 1 Mark
8.
Complete the figure and find out the nature of the image. (AS6) 2 Marks
9.
Complete the figure and indicate the position of image. (AS5) 2 Marks
10.
Answer the questions given below.
(i) Write the characteristics of the image which formed in the above diagram.
(ii) Depending upon the above ray diagram how can a convex lens useful in the real life. (AS4) 2 Marks
11. When we perform experiments with lens, we cannot decide the image distance when virtual images are formed. Is this information correct or wrong? Explain with reasons. (AS1) 2 Marks
12. Mention the differences between real and virtual images. (AS1) 2 Marks
13. Draw a ray diagram shows an image of infinite distance with a convex lens.
(AS5) 2 Marks
14. Imagine that lenses were not known to human beings, Guess the consequences.
(AS2) 2 Marks
15.
From the above figures answer the questions.
(i) State the positions of object and image from the above two cases.
(ii) From the above two cases write the characteristics of image. (AS4) 4 Marks
16. Draw any four ray diagrams for an object which placed on principal axis using convex lens. (AS5) 4 Marks
17. Calculate the power of the lens and write the correct signs. (AS1) 4 Marks
'f' of the lens |
Type of the lens |
power (in diopters) |
50 cm |
convex |
|
40 cm |
concave |
|
80 cm |
convex |
|
125 cm |
concave |
|
18. An object is placed 27 cm a way from a convex lens. Calculate the image distance and comment on its nature if the focal length of the lens is 14 cm. (AS1) 4 Marks
19. Four friends of a class found the focal length of a lens experimentally. The values are 12.1 cm, 12.2 cm, 12.3 cm, 12.05 cm. They discussed the reason for variations in values. Mention those reasons. (AS1) 2 Marks
20. Draw the path of a light ray travelling through a curved surface from a rearer medium to denser medium. (AS5) 2 Marks
21. Draw the figures of lens which have one curved surface. (AS5) 2 Marks
22. Where should be the object placed if we have to use the convex lens as a magnifying lens. (AS1) 1 Mark