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प्रश्न
What type of image is always made by a concave lens?
उत्तर
A concave lens always forms a virtual and erect image.
संबंधित प्रश्न
Where must the object be placed for the image formed by a converging lens to be:
virtual, upright and larger than the object?
An illuminated object is placed at a distance of 20 cm from a converging lens of focal length 15 cm. The image obtained on the screen is:
(a) upright and magnified
(b) inverted and magnified
(c) inverted and diminished
(d) upright and diminished
A converging lens of focal length 5 cm is placed at a distance of 20 cm from a screen. How far from the lens should an object be placed so as to form its real image on the screen?
An object is placed 10 cm from a lens of focal length 5 cm. Draw the ray diagrams to show the formation of image if the lens is diverging.
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?
The power of a concave lens is 10 D and that of a convex lens is 6 D. When these two lenses are placed in contact with each other, the power of their combination will be :
(a) +16 D
(b) +4 D
(c) −16 D
(d) −4 D
A virtual diminished image is formed when an object is placed between the optical centre and the principal focus of a lens.
(i) Name the type of lens which forms the above image.
(ii) Draw a ray diagram to show the formation of the image with the above stated characteristics.
Define the principal focus of a concave lens.
Distinguish between Concave lens and Convex Lens.
Give two characteristics of the image formed by a concave lens.
