Available Answers

1. 1.

   State, true or false. If false, write the correct statement.

   1. A simple microscope is sometimes known as a reading glass.
   2. The image formed by a magnifying glass is real and enlarged.
   3. While using a simple microscope, the object is kept between F and O.
   4. Compound microscope is used to see the objects at large distances.
   5. Image formed in a compound microscope is virtual and magnified,
   6. To observe celestial objects like moon, stars. etc., we use a telescope.
   7. A telescope gives an inverted and diminished image of distant objects.
   8. To get sharp images of objects at different distances, the focal length of the eye-lens changes on its own.
   9. To get sharp images of objects of different distances. the distance between the lens and the film of a camera is adjusted.
   10. Short-sightedness means, that the eye can see the nearby objects clearly and long-sightedness means, that the eye see the distant objects clearly.
2. 2.

   Fill in the blanks :

   1. The image formed by a magnifying glass is _________________.
   2. The image formed by a camera is _________________.
   3. The image formed by an eye is _________________.
   4. In a simple microscope, object is placed between _________________ and _________________.
   5. The image formed in an eye is _________________, whereas image formed in a camera is _________________.
   6. Compound microscope is used to see _________________.
   7. A telescope is used to see _________________.
   8. The least distance of normal vision is _________________.
   9. _________________ lens is used to correct myopia and _________________ lens is used to correct hypermetropia.
   10. The lens used in a camera is _________________.
   11. When both the lenses are used in a telescope, it is called _________________.
3. 3.

   What is the 'power of accommodation' of an eye?

4. 4.

   What are the common defects of vision of a human eye ? How can these defects be corrected by spectacles?

5. 5.

   Write one similarity and one dissimilarity between an eye and a camera.

6. 6.

   What is meant by least distance of normal vision ? What is its value ?