Home
Class 12
PHYSICS
A plano-covex lens is made of a material...

A plano-covex lens is made of a material of refractive index n. When a small object is placed 30cm away in front of the curved surface of the lens, an image of double the size of the object is produced. Due to reflection from the convex surface of the lens, another faint image is observed at a distance of 10 cm away from the lens. Which of the following statement (s) is (are) true?

A

The refractive index of the lens is 2.5

B

The radius of curvature of the convex surface is 45 cm

C

The faint image is erect and real

D

The focal length of the lens is 20 cm

Text Solution

Verified by Experts

The correct Answer is:
A, D
Promotional Banner

Topper's Solved these Questions

  • GEOMETRICAL OPTICS

    MOTION|Exercise Exercise - 4 | Level-I|25 Videos

  • FLUID

    MOTION|Exercise Exercise-4 level-II|5 Videos

  • GRAVITATION

    MOTION|Exercise Exercise - 4 Section - B Previous Years Problems|15 Videos

Similar Questions

Explore conceptually related problems

A plano-convex lens is made of material having refractive index 1.5. The radius of curvature of curved surface is 60 cm. The focal length of the lens is ______ cm.

A plano-convex lens is made of glass of refractive index 1.6. the radius of curvature of its curved surface is 30 cm. What is the focal length of the lens ?

A plano-convex lens of focal length 30 cm has its plane surface silvered. An object is placed 40 cm from the lens on the convex side. The distance of the image from the lens is

An object is placed in front of a convex lens of focal length 12 cm. If the size of the real image formed is half the size of the object, calculate the distance of the object from the lens.

When an object is placed at a distance of 36 cm from a convex lens, an image of the same size as the object is formed. What will be the nature of image formed when the object is formed. What will be the nature of image formed when the object is placed at a distance of: a) 10 cm from the lens? b) 20 cm from the lens?

A convex lens of focal length 16 cm forms a real image double the size of the object. The image distance of the object from the lens is

A convex lens produces a real image m times the size of the object. What will be the distance of the object from the lens ?

The focal length of convex lens is 20 cm. If an object of height 4 cm is placed at a distance of 30 cm from the lens, find: The height of the image

MOTION-GEOMETRICAL OPTICS-Exercise - 4 | Level-II
  1. A transparent thin film of uniform thickness and refractive index n(1)...

    Text Solution

    |

  2. Consider a concave mirror and a convex lens (refractive index 1.5) of ...

    Text Solution

    |

  3. Two identical glass rods S(1) and S(2) (refractive index=1.5) have one...

    Text Solution

    |

  4. A monochromatic beam of light is incident at 60^@ on one face of an eq...

    Text Solution

    |

  5. Light guidance in an optical fibre can be understood by considering a ...

    Text Solution

    |

  6. Light guidance in an optical fibre can be understood by considering a ...

    Text Solution

    |

  7. A parallel beam of light is incident from air at an angle alpha on the...

    Text Solution

    |

  8. A plano-covex lens is made of a material of refractive index n. When a...

    Text Solution

    |

  9. A transparent slab of thickness d has a refractive index n(z) that inc...

    Text Solution

    |

  10. A small object is placed 50 cm to the left of a thin convex lens of fo...

    Text Solution

    |

  11. The diameter of a plano convex lens is 6 cm and thickness at the centr...

    Text Solution

    |

  12. For an isosceles prism of angle A and refractive index mu it is found ...

    Text Solution

    |

  13. A monochromatic light is travelling in a medium of refractive index n ...

    Text Solution

    |

  14. Sunlight of intensity 1.3kW m^(–2) is incident normally on a thin conv...

    Text Solution

    |

  15. A wire is bent in the shape of a right angled triangle and is placed i...

    Text Solution

    |

  16. Consider two palne convex lanse of same radius of curvature and refrec...

    Text Solution

    |

  17. A planar structure of length L and width W is made of two different op...

    Text Solution

    |

  18. Three glass cylinders of equal height H = 30 cm and same refractive in...

    Text Solution

    |

  19. A prism is shown in the figure with prism angle 75^(@) and refractive ...

    Text Solution

    |

  20. An optical bench has 1.5 m long scale having four equal divisions in e...

    Text Solution

    |