Page 180 - Science Class 08

5. Explain the construc on of microscope.
6. Explain human eye with diagram.

H. Long answer ques ons.
1. What is a lens? Which four pieces is it made of? How many curved surfaces must it have at
least and what are its two chief types? Name them.
2. What is convex lens? How many types of images can be formed by it? Explain with
diagrams.
3. What is a concave lens? What types of images does it form? Explain through a diagram.
4. What are op cal devices? About which three such devices have you read in this lesson?
Name them and write in detail about any one of them.

5. What do you know about the human eye and its common disorders? Explain with diagram.
6. What steps should be taken for the proper care of the eyes?
7. Write notes on :
(a) principal axis (b) op cal centre (c) focus

Project
Project ActivityActivityActivity
Project
Project Activity
A. Make a chart showing the working of the eye and its common disorders. Hang it in you class-
room.
B. Label the different parts of the human eye in the picture given below.

HO
HO
HOTSTSTS
HOTS
A. Will a spectrum be formed if blue light falls on a prism? Give reasons.
B. Can a glass slab bend different coloured lights by different amounts?

180 Science-8