A converging bundle of light rays in the shape of cone with a vertex angle of 45 falls on a circular diaphragm of 20 cm diameter. A lens with power 5 D is fixed in the diaphragm. Diameter of face of lens is equal to that of diaphragm. If the vertex angle of new cone is ' then tan ’ |
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(a) |
1.5 |
(b) |
2 |
(c) |
3 |
(d) |

A converging bundle of light rays in the shape of cone with a vertex angle of 45 falls on a circular diaphragm of 20 cm diameter. A lens with power 5 D is fixed in the diaphragm. Diameter of face of lens is equal to that of diaphragm. If the vertex angle of new cone is ' then tan ’ |
|||||||

(a) |
1.5 |
(b) |
2 |
(c) |
3 |
(d) |

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