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A convex lens makes a real image 4 cm lo...

A convex lens makes a real image 4 cm long on a screen. When the lens is shifted to a new position without disturbing the object, we again get a real image on the screen which is 16 cm tall. The length of the object must be

A

8 cm

B

10 cm

C

12 cm

D

6 cm

Text Solution

Verified by Experts

The correct Answer is:
A
`OJ=sqrt(I_(1)I_(2))`
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NARAYNA-RAY OPTICS AND OPTICAL INSTRAUMENTS -EXERCISE-2 (H.W)(LENSES & THEIR COMBINATIONS)
  1. A slide projector gives magnification of 10. If it projects a slide of...

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  2. The radius of curvature of a thin planoconvex lens is 10 cm and the re...

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  3. The graph between object distance u and image distance v for a lens gi...

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  4. In the displacement method a conves lens is placed in between an objec...

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  5. A convex lens makes a real image 4 cm long on a screen. When the lens ...

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  6. A convex lens of focal length 50 cm, a concave lens of focal length 50...

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  7. Arrange the following combinations in the increasing order of focal le...

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  8. The image of an object, formed by a plano-convex lens at a distance of...

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  9. The radius of curvature of the convex surface of a planoconvex lens is...

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  10. An equiconcave lens having radius of curvature of each surface 20 cm h...

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  11. If R(1) and R(2) are the radii of curvature of double convex lens made...

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  12. A concave lens of glass, refractive index 1.5 has both surfaces of sam...

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  13. A thin equi-convex lens is made of glass of refractive index 1.5 and i...

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  14. A convex Lens of focal Length "0.15m" is made of refractive "(3)/(2)" ...

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  15. A diverging lens of focal length 10 cm having refractive index 1.5 is ...

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  16. A plano convex lens a thickness of 4 cm. Its radius of curvature is 20...

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  17. Two equi convex lenses each of focal lengths 20 cm and refractive inde...

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  18. If R1 and R2 are the radii of curvature of a double convex lens. The l...

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  19. A thin convergent glass lens (mug=1.5) has a power of +5.0D. When this...

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  20. The refractive index of a material of a plano concave lens is 5/3. Its...

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