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Ray coming from an object situated at in...

Ray coming from an object situated at infinity, fall on a convex lens and an image is formed at a distance of 16 cm from the lens. When a concave lens is kept in contact with the convex lens, the image is formed at a distance of 20 cm from the lens combination. Calculate the focal length of the concave lens.

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The correct Answer is:
`-80 cm`
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SL ARORA-RAY OPTICS-Problems For Self Practice
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  6. The refractive index of the material of a prism of 60^(@) angle for ye...

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  7. A ray of light incident at 49^(@) on the face of an equilateral prism ...

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  8. A glass prism has a refracting angle of 60^@. The angle of minimum dev...

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  9. A ray incident normally on one face of a right-angled isosceles glass ...

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  10. As shown in Fig. PQ is a ray incident on prism ABC. Show the correspon...

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  11. Show that a light ray will pass through an equilateral glass prism (mu...

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  12. A ray of light falls on a normally on a refracting face of a prism. Fi...

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  13. A ray of light is incident on the glass prism at an angle of 40^(@). F...

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  14. A ray of light falls on a glass prism at a angle of incidence of 30^(@...

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  15. A ray of light suffers a deviation of 3.2^(@) on passing through a thi...

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  16. A thin glass prism placed in air produces minimum deviation of 4^(@) i...

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  17. White light is passed through a prism of 5^(@). If refractive indices ...

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  18. The deviation caused for red, yellow and violet colours for crown glas...

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