Combinations of Mirrors and Thin Lenses

IMPORTANT

Combinations of Mirrors and Thin Lenses: Overview

This topic covers concepts, such as, Thin Lenses in Contact, Silvered Lens & Cutting of Lens etc.

Important Questions on Combinations of Mirrors and Thin Lenses

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Which of the following can form diminished, virtual and erect image of your face

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A flat mirror M is arranged parallel to the wall W at a distance l from it. The light produced by a point source S kept on the wall is reflected by the mirror and produces a light spot on the wall. The mirror moves with velocity v towards the wall.

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It is desired to make an achromatic combination of two lenses (L1 & L2) ω1 and ω2 (<ω1). If the combination of lenses is converging then

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A planoconvex lens, when silvered at its plane surface is equivalent to a concave mirror of focal length 28 cm. When its curved surface is silvered and the plane surface not silvered, it is equivalent to a concave mirror of focal length 10 cm, then the refractive index of the material of the lens is

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An object is placed in front of a thin convex lens of focal length 30 cm and a plane mirror is placed 15 cm behind the lens. If the final image of the object coincides with the object, the distance of the object from the lens is

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A object is placed at a distance of 15 cm from a convex lens of focal length 10 cm. On the other side of the lens, a convex mirror is placed at its focus such that the image by the combination coincides with the object itself. The focal length of the convex mirror is

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A double convex lens has focal length of 25.0 cm in air. The radius of one of the surfaces is double of the other. Find the radii of curvature, if the refractive index of the material of the lens is 1.5.

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Which of the following expression is correct for :

Taking the rays as incident from a medium of refractive index   n 1  to another of refractive index   n 2

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An illuminated object and a screen are placed 90 cm apart. The focal length and nature of the lens required to produce a clear image on the screen, twice the size of the object would be:

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A given ray of light suffers minimum deviation in an equilateral prism P. Additional prism Q and R of identical shape and of the same material as P are now added as shown in the figure. The ray will now suffer

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An eye specialist prescribes spectacles having a combination of convex lens of focal length 40 cm in contact with a concave lens of focal length 25 cm. The power of this lens combination in diopters is

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Spherical aberration in a thin lens can be reduced by

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A thin plane convex glass lens μ=1.5 has its plane surface silvered and R is the radius of curvature of the curved part. Then which of the following ray diagram is the correct representation for an object placed at O.

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A biconvex lens of radius of curvature Ris made up of a variable refractive index μ=21+|y|d. Assume 2 d<<R. A point object is placed at R=1 m on the principal axis as shown in figure. If the spread of image lies over a span of n meter along the axis, then find the value of n.

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The radius of curvature of convex surface of a Plano-convex lens is 15 cm. The R.I. of material of lens is 32. When kept in air has focal length f. If plane surface is silvered and lens is kept in a large medium of R.I. =2, it behave as a mirror of power P

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A tube of length 30 cm has its inner lateral surface blackened. Two lenses of focal lengths 10 cm and 20 cm are fixed at the ends of the tube. For same beam, intensities of spots on screen are I1 and I2 for arrangement 1 and arrangement 2. If the ratio of I2 : I1 is of the form N2, find N.

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A real image of an object is formed at a distance of 20 cm from a lens. On putting another lens in contact with it, image is shifted 10 cm towards the combination. The power of the lens is _____ D.

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Consider a concave mirror and a convex lens (refractive index = 1.5) of focal length 10 cm each, separated by a distance of 50 cm in air (refractive index = 1), as shown in the figure. An object is placed at a distance of 15 cm from the mirror. Its erect image, formed by this combination, has magnification M1 . When the set-up is kept in a medium of refractive index 76 , the magnification becomes M2. The magnitude M2M1 is

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A bi-convex lens is formed with two thin plano-convex lenses as shown in the figure. The refractive index n of the first lens is 1.5 and that of the second lens is 1.2. Both the curved surfaces are of the same radius of curvature, R=14 cm. For this bi-convex lens, for an object distance of 40 cm, the image distance will be,

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A combination of two thin convex lenses of focal length 0.3 m and 0.1 m will have minimum spherical and chromatic aberrations if
the distance between them is