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Three lenses in contact have a combined ...

Three lenses in contact have a combined focal length of 12 cm. When the third lens is removed, the combined focal length is `(60)/(7)` cm. The third lens is

A

A converging lens of focal length 30 cm

B

A converging lens of focal length 60 cm

C

A diverging lens of focal length 30 cm

D

A diverging lens of focal length 60 cm

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The correct Answer is:
C
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AAKASH INSTITUTE ENGLISH-RAY OPTICS AND OPTICAL INSTRUMENTS-EXERCISE
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  10. A lens made of material of Refractive index mu(2) is surrounded by a m...

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  11. A light ray is incident normally on one of the refracting faces of a p...

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  12. If a light ray incidents normally on one of the faces of the prism of ...

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  18. Suppose a small angled prism of 6^(@) deviates a ray through 3^(@), th...

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  20. If a is the size of scatterer and lamda is the wavelength of light the...

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