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प्रश्न
A lens forms an upright and magnified image of an object State whether the image is real or virtual
उत्तर
Virtual.
APPEARS IN
संबंधित प्रश्न
(a) Draw a ray diagram to show the formation of image by a concave lens when an object is placed in front of it.
(b) In the above diagram mark the object distance (u) and the image distance (v) with their proper signs (+ve or –ve as per the new Cartesian sign convention) and state how these distances are related to the focal length (f) of the concave lens in the case.
(c) Find the nature and power of a lens which forms a real and inverted image of magnification –1 at a distance of 40 cm from the optical centre.
Which of the following lenses would you prefer to use while reading small letters found in a dictionary?
Complete the following table:
| Instrument | Number of Convex Lenses |
Use |
| Simple Microscope | .............. | .............. |
| Compound Microscope | .............. | .............. |
| Telescope | .............. | .............. |
A convex lens has a focal length of 10 cm. At which of the following position should an object be placed so that this convex lens may act as a magnifying glass?
(a) 15 cm
(b) 7 cm
(c) 20 cm
(d) 25 cm
A convex lens of focal length 0.10 m is used to form a magnified image of an object of height 5 mm placed at a distance of 0.08 m from the lens. Calculate the position, nature and size of the image.
A camera fitted with a lens of focal length 50 mm is being used to photograph a flower that is 5 cm in diameter. The flower is placed 20 cm in front of the camera lens.
At what distance from the film should the lens be adjusted to obtain a sharp image of the flower?
An image formed on a screen is three times the size of the object. The object and screen are 80 cm apart when the image is sharply focussed.
State which type of lens is used.
How will you decide whether a given piece of glass is a concave lens, convex lens, or a plane glass plate?
Out of the two lenses one concave and the other convex state which is a convergent or a divergent type of a lens. Give a reason for your answer.
What happens to the image formed by a convex lens if its lower part is blackened?
