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A concave lens is placed in the path of ...

A concave lens is placed in the path of a uniform parallel of beam of light falling on a screen as shown . Then

A

(a)Intensity of light will be the same every where on the screen

B

(b)Intensity in region AB will be smaller that what it would be in the absence of the lens

C

(c)In the region AC and BD , the intensity will be smaller than what it would be in the absence of the lens

D

(d)In the region AC and BD, the intensity will be greater than what it would be in the absence of the lens

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The correct Answer is:
B,D
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ALLEN -GEOMETRICAL OPTICS-EXERCISE-2
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  2. A man of height 170cmwants to see his complete image in a plane mirror...

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  3. Two plane mirrors at an angle such that a ray incident on a mirror und...

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  4. If the equation of mirror is given by y= 2//pi "sin"pix (y gt 0 , 0 le...

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  5. In the fig. shown consider the first reflection at the plane mirror an...

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  6. The figure shows a ray incident a angle i=pi//3 of the plot drawn show...

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  7. A ray of light is incident normally on one face of 30^(@) - 60^(@) - 9...

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  8. A curved surface of radius R separates two medium of refractive indice...

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  9. A curved surface of radius R separates two medium of refractive indice...

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  10. A curved surface of radius R separates two medium of refractive indice...

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  11. An object O is kept infront of a converging lens of focal length 30 cm...

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  12. A converging lens of focal length f(1) is placed in front of and coaxi...

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  13. Choose the correct alternative corresponding to the object distance 'u...

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  14. An object and a screen are fixed at a distance d apart. When a lens of...

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  15. A diminished image of an object is to be obtained on a screen 1.0 m fr...

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  16. A convex lens forms an image of an object on a screen. The height of t...

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  17. A ray is incident on the first prism at an angle of incidence of 53^(@...

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  18. For refractin of light through a prism

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  19. Two lenses in contact made of materials with dispersive powers in the ...

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  20. A concave lens is placed in the path of a uniform parallel of beam of ...

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