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प्रश्न
A converging lens is used to produce an image of an object on a screen,object on a screen. What change is needed for the image to be formed nearer to the lens?
(a) increase the focal length of the lens
(b) insert a diverging lens between the lens and the screen
(c) increase the distance of the object from the lens
(d) move the object closer to the lens
उत्तर
Increase the distance of the object from the lens
As the object moves away from the lens, the image gets closer to the lens.
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संबंधित प्रश्न
If the numerical value of the power of this lens is 10 D, what is its focal length in the Cartesian system ?
How would you alter the above diagram to show how a converging lens can produce a beam of parallel rays of light.
Copy and complete the diagram below to show what happens to the rays of light when they pass through the concave lens:
A ray of light is going towards the focus of a concave lens. draw a ray diagram to show the path of this ray of light after refraction through the lens.
An object 60 cm from a lens gives a virtual image at a distance of 20 cm in front of the lens. What is the focal length of the lens? Is the lens converging or diverging? Give reasons for your answer.
A concave lens has focal length 15 cm. At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens? Also find the magnification produced by the lens.
The power of a converging lens is 4.5 D and that of a diverging lens is 3 D. The power of this combination of lenses placed close together is :
(a) +1.5D
(b) +7.5D
(c) −7.5D
(d) −1.5D
The power of a lens is negative. State whether it is convex or concave.
Copy the following figure and complete it to show the formation of the image of the object AB. Name the lens used in the figure.
Convex magnifying glass is called divergent magnifying glass and concave magnifying glass is called converging magnifying glass.
