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प्रश्न
In the following diagram, L1 and L2 are the two convex lense placed at separation equal to the sum of focal lengths of the two lenses. A and B are the two rays of light incident on the lens L1. Complete the path of rays till they emerge out of the lens L2.

What principles have you used in completing the diagram?
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उत्तर
The complete ray diagram is shown below.

The following two principles have been used in completing the diagram:
(i) A ray of light incident parallels to the principal axis after refraction from the convey lens passes through the focus.
(ii) A ray of light incident on the convex lens through its focus after refraction becomes parallel to the principal axis of the lens.
संबंधित प्रश्न
A ray of light incident on a lens parallel to its principal axis, after refraction passes through or appears to come from ______.
A ray of light incident at the optical centre of lens, passes undeviated after refraction.
In the following diagram the object and the image formed by the respective lenses are shown. Complete the ray diagram, and locate the focus. Find the focal length of the lens.

In the following diagram , the object and the image formed by the respective lenses are shown. Complete the ray diagram, and locate the focus. Find the focal length of the lens.

Make the correct choices in the following items:
lf the image can be focused on a screen it must be
(a)A ray of light is incident at 45° on the face of
(i) A rectangular block of glass.
(ii) A 600 glass prism.
(b) Draw a sketch showing how the ray of monochromatic ray of light passes through glass in each case.
(c) With the aid of a diagram, explain how the face of a right angled prism may totally reflect incident on it.
(d) A thick plane mirror produces several faint images in addition to a prominent one. Draw a ray diagram showing how reflection and refraction produce all these images.
(e) Fig. represents a stone S at the bottom of a pond of water. Using the two rays, as shown, complete the ray diagram to show where the image of the stone appears when viewed from E.

(f) What is a''mirage'? Explain with the help of a diagram.
(g) A man observes the bottom of a swimming pool of 3 m depth. If the refractive index of water is 1.3, what is the apparent depth of water?
(h) When a ray of light undergoes refraction through a glass slab and when it emerges it is displaced laterally (Fig). What are the factors on which the lateral displacement depends?

(i) Fig. shows three rays of light OA, OB and OC passing from water to air, making angles 490, 410 and 350 with the horizontal surface respectively. Draw an approximate path of the emergent ray for each. (Critical angle of water is 490.)

A lens forms the image of an object placed at a distance of 45 cm from it on a screen placed at a distance 90 cm on the other side of it. Name the kind of lens.
When does a ray of light falling on a lens pass through it undeviated?
Draw a ray diagram to show the image formed by a convex lens when the object is placed between F and 2F.
