Home
Class 12
PHYSICS
A thin convex lens of focal length 'f' i...

A thin convex lens of focal length 'f' is put on a plane mirror as shown in the figure . When an object is kept at a distance 'a' from the lens - mirror combination , its image is formed at a distance `(a)/(3)` in front of the combination . The value of 'a' is :-

Text Solution

Verified by Experts

The correct Answer is:
D
`(1)/(f_("eq")) = (1)/(f_(m)) - (2)/(
Promotional Banner

Topper's Solved these Questions

  • GEOMETRICAL OPTICS

    ALLEN|Exercise EXERCISE-05 (B)|35 Videos

  • GEOMETRICAL OPTICS

    ALLEN|Exercise MCQ|5 Videos

  • GEOMETRICAL OPTICS

    ALLEN|Exercise EXERCISE-04[B]|18 Videos

  • CURRENT ELECTRICITY

    ALLEN|Exercise All Questions|427 Videos

  • GRAVITATION

    ALLEN|Exercise EXERCISE 4|9 Videos

Similar Questions

Explore conceptually related problems

A convex lens of focal length f produces a virtual image n times the size of the object. Then the distance of the object from the lens is

An object is kept at a distance 20 cm from a convex mirror of focal length 20 cm. The image will form at

A convex lens of focal length f forms an image which is 13/ times the size of the object. Then, the distance of object from the lends is

A biconvex lens of focal length 15 cm is in front of a plane mirror. The distance between the lens and the mirror is 10 cm. A small object is kept at a distance of 30 cm from the lens. The final image is

An object, a convex lens of focal length 20 cm and a plane mirror are arranged as shown in the figure. How far behind the mirror is the second image formed?

A convex lens of focal length 15 cm is placed on a plane mirror. An object is placed at 30 cm from the lens. The image is

ALLEN-GEOMETRICAL OPTICS-EXERCISE-05 (A)
  1. Let the x-z plane be the boundary between two transparent media. Mediu...

    Text Solution

    |

  2. A car is fitted with a convex side-view mirror of focal length 20 cm. ...

    Text Solution

    |

  3. When monochromatic red light is used instead of blue light in a convex...

    Text Solution

    |

  4. A beaker contains water up to a height h(1) and kerosene of height h(2...

    Text Solution

    |

  5. An object 2.4 m in front of a lens forms a sharp image on a film 12 cm...

    Text Solution

    |

  6. The graph between angle of deviation (delta) and angle of incidence (i...

    Text Solution

    |

  7. Diameter of a plano-convex lens is 6cm and thickness at the centre is ...

    Text Solution

    |

  8. A thin convex lens made from crown glass (mu = 3//2) has focal length ...

    Text Solution

    |

  9. A green light is incident from the water to the air - water interface ...

    Text Solution

    |

  10. You are asked to design a shaving mirror assuming that a person keeps ...

    Text Solution

    |

  11. A thin convex lens of focal length 'f' is put on a plane mirror as sho...

    Text Solution

    |

  12. Assuming human pupil to have a radius of 0.25 cm and a comfortable vie...

    Text Solution

    |

  13. Monochromatic light is incident on a glass prism of angle A. If the re...

    Text Solution

    |

  14. An obsever looks at a distant tree of height 10m with a telescope of m...

    Text Solution

    |

  15. In an experiment for determination of refractive index of glass of a p...

    Text Solution

    |

  16. To find the focal length of a convex mirror , a student records the fo...

    Text Solution

    |

  17. A convex lens of focal length 30 cm , a concave lens of focal length 1...

    Text Solution

    |

  18. Two stars are 10 light years away from the earth. They are seen throug...

    Text Solution

    |

  19. To determine refractive index of glass slab using a travelling microsc...

    Text Solution

    |

  20. A hemispherical glass body of radius 10 cm and refractive index 1.5 is...

    Text Solution

    |