Advertisements
Advertisements
प्रश्न
An object is placed at a distance of 60 cm from a concave lens of focal length 30 cm.
(i) Use the lens formula to find the distance of the image from the lens.
(ii) List four characteristics of the image (nature, position, size, erect/inverted) formed by the lens in this case.
(iii) Draw a ray diagram to justify your answer of the part (ii).
उत्तर
We have,
(i) Object distance, u= —60 cm Focal length of the concave lens, f= —30 cm Using lens formula,
`1/"v"-1/"u" = 1/"f"`
`1/"v" - 1/((-60)) =1/((-30))`
`1/"v"=(-1)/30-1/60`
`1/"v"=(-3)/60`
v = -20 cm
The image will be formed at a distance of 20 cm in front of the lens.
(ii) Nature of the image is virtual. The position of the image is between F1 and optical center 0. Size of the image is diminished. The image is Erect.
(iii)
संबंधित प्रश्न
If the numerical value of the power of this lens is 10 D, what is its focal length in the Cartesian system ?
What type of image is always made by a concave lens?
Give the position, size and nature of image of formed by a concave lens when the object is placed:
anywhere between optical centre and infinity.
When an object is placed 10 cm in front of lens A, the image is real, inverted, magnified and formed at a great distance. When the same object is placed 10 cm in front of lens B, the image formed is real, inverted and same size as the object.
What is the nature of lens A?
Name one of the common defects of vision and the type of lens used to remove it.
How will you differentiate between a convex and a concave lens by looking at
- a distant object,
- a printed page?
Distinguish between concave and convex lens.
In figure give below of thin concave lens, F1 and F2 are its foci, complete the path of the given ray of light after it emerges out of the lens.
Distinguish between Concave lens and Convex Lens.
