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प्रश्न
An object is held 20 cm away from a converging lens of focal length 10 cm. Find the position of the image formed.
उत्तर
Given:Converging lens, f = 10 cm and u = -20cm
`1/f = 1/v - 1/u`
`∴ 1/v = 1/f + 1/u`
`-> 1/v = 1/10 + 1/(-20) = 1/10 - 1/20`
`-> 1/v = 1/(20 cm)`
∴ v = 20 cm
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संबंधित प्रश्न
A student is using a convex lens of focal length 10 cm to study the image formation by a convex lens for the various positions of the object. In one of his observations, he may observe that when the object is placed at a distance of 20 cm from the lens, its image is formed at (select the correct option)
(A) 20 cm on the other side of the lens and is of the same size, real and erect.
(B) 40 cm on the other side of the lens and is magnified, real and inverted.
(C) 20 cm on the other side of the lens and is of the same size, real and inverted.
(D) 20 cm on the other side of the lens and is of the same size, virtual and erect.
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(A) lens and the object only
(B) lens and the screen only
(C) object and the image only
(D) lens and the object and also between the object and the image
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(b) less than 1
(c) equal to 1
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(b) at the centre of curvature
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