Advertisements
Advertisements
प्रश्न
What is a lens?
Advertisements
उत्तर
A lens is a transparent refracting medium bounded by two curved surfaces which are generally spherical.
संबंधित प्रश्न
In figure, (a) and (b), F1 and F2 are the two foci of thin lenses and AB is the incident ray. Complete the diagram to show the path of the ray AB after refraction through each lens.
![]() |
| (a) |
![]() |
| (b) |
Study the diagram shown in Fig. 5.56
Where is the image formed?

The diagram given below shows the position of an object OA in relation to a converging lens L whose foci are at F1 and F2.

- Draw two rays to locate the position of the image.
- State the position of the image with reference to the lens.
- Describe three characteristics of the image.
- Describe how the distance of the image from the lens and its size change as the object is moved towards F1.
The diagram given below shows the position of an object OA in relation to a converging lens whose foci are at F1 and F2.

Describe how the distance of the image from the lens and the size of the image change as the object is moved towards F1.
A ray of light incident at the optical centre of lens, passes undeviated after refraction.
State the condition of the following:
A ray passes undeviated through the lens.
Fig shows an object PQ placed on the principle axis of a lens L. The two foci of the kens are F1 and f2. The image formed by the lens is erect, Virtual and dimnished.

(i) Draw the outline ofthe lens L used and Named it.
(ii) Draw a ray of light starting from Q and passing through O. show the same ray after refraction by the lens.
(iii) Draw another ray from Q Which is incident parallel to the principle axis and show how it emerges after refraction from the lens.
(iv) Locate the final image formed.
Make the rrect choices in the following items :
ln fig, , a real image of a point objert O is formed, Which of the following statements is true about each of the arrangements?

(i) The object is at the principle focus of the lens
(ii) The focal length of the lens is 17 cm
(iii) lf the mirror is moved so that it is 6 cm from the lens image will also move
Make the correct choices in the following items :
A lens used as a magnifying glass
(i) ls a diverging lens
(ii) Produces a virtual image
(iii) ls placed with the object nearer the lens than the principle focus
Name the subjective property of light related to its wavelength.


