Home
Class 12
PHYSICS
a. Figure (a) shows the optical axis o...

a. Figure (a) shows the optical axis of a lens, the point source of light A, and its virtual image `A^(')` . Trace the rays to find the position of the lens and of its focuses. What type of lens is it?

b. Solve the problem similar to the previous one using Figure.

Text Solution

Verified by Experts

The correct Answer is:
C
First draw a ray AA' until it intersects with the
principal optical axis and find the centre of the lens
C. Since, the virtual image is magnified, the lens is
convex.

Draw a ray AB parallel to the principal optical axis.
It is refracted by the lens so that it passes through its
focus and its continuation passes through the virtual
image. The ray A'B intersects the principal optical
axis at point F, the focus of the lens.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • REFRACTION OF LIGHT

    DC PANDEY|Exercise Level 2 Comprehension Based|3 Videos

  • REFLECTION OF LIGHT

    DC PANDEY|Exercise Subjective|9 Videos

  • SEMICONDUCTORS

    DC PANDEY|Exercise Subjective|12 Videos

Similar Questions

Explore conceptually related problems

Given an optical axis MN and the positons of a real object AB and its image A 'B' , detormine diagramatically the positon of the lens (its optical centre O ) and its foci, it it a converging or diverging lens? Is the image real or virtual?

A lens placed at a distance of 20cm from a object produces of virtual Image 2//3 the size of the object.Find the position of the image,kind of lens and its focal length.

Knowledge Check

  • A lens is placed between a source of light and a wall. It forms images of are A_(1) and A_(2) on the wall, for its two different positions, the area of the source of light is

    A
    `sqrt(A_(1)A_(2))`
    B
    `(A_(1)+A_(2))/2`
    C
    `(A_(1)-A_(2))/2`
    D
    `(1)/A_(1)+(1)/A_(2)`

  • A point source of light is moving at a rate of 2 cm-s^(-1) towards a thin convex lens of focal length 10 cm along its optical axis. When the source is 15 cm away from the lens the image is moving at -

    A
    `4 cm-s^(-1)` towards the lens
    B
    `8 cm-s^(-1)` towards the lens
    C
    `4 cm-s^(-1)` away from the lens
    D
    `8 cm-s^(-1)` away from the lens

    • Similar Questions

    Explore conceptually related problems

    A glass wedge with a small angle of refraction theta is placed at a certain distance from a converging lens with a focal length f ,one surface of the wedge being perpendicular to the optical axis of the lens. A point sources S of light is on the other side of the lens at its focus. The rays reflected from the wedge (not from base) produce, after refraction in the lens , two images of the source displaced with respect to each other by d. Find the refractive index of the wedge glass. [Consider only paraxial rays.]

    Find the position of the image formed by the lens combination given in the following figure :

    AB is the optic axis of a lens. Lens is not shown in the figure. O and I are the position of object and image. Then match of following.

    In Figure. , the length of object AB is 9cm. Find the nature and position of the final image and also its length. Assum that each lens is a thin lens.

    By means of plotting find : (a) the path of a ray of light beyound thin converging and diverging lenses (Fig. where OO' is the optical axis, F and F' are the front and rear focal points), (b) the position of a thin lens and its focal points if the position of the optical axis OO' and the positions of the cojugate3 points P, P (see Fig.) are knows , the media on both sides of the lenses are identical, (c ) the path of ray 2 beyond the converging and diverging lenses (Fig. ) if the path of ray 1 and the positions of the lens and of its optical axis OO' are all known, the media on both sides of the lenses are identical.

    Converging light rays are falling on a convex lens. If the focal length of the lens is 30 cm, then find the position of the image.

    Home
    Profile