Home
Class 12
PHYSICS
Alens is placed between a source of ligh...

Alens is placed between a source of light and a wall. It forms images of are `A_(1)` and `A_(2)` on the wall, for its two different positions, the area of the source of light is

A

`(A_(1)-A_(2))/2`

B

`1/A_(1)+1/A_(2)`

C

`sqrt(A_(1)A_(2))`

D

`(A_(1)+A_(2))/2`

Text Solution

Verified by Experts

The correct Answer is:
C
Promotional Banner

Topper's Solved these Questions

  • RAY OPTICS AND OPTICAL INSTRUMENTS

    AAKASH INSTITUTE|Exercise ASSIGNMENT (SECTION - D)|16 Videos

  • RAY OPTICS AND OPTICAL INSTRUMENTS

    AAKASH INSTITUTE|Exercise ASSIGNMENT (SECTION - B)|30 Videos

  • PHYSICAL WORLD

    AAKASH INSTITUTE|Exercise ASSIGNMENT (Section-B)|5 Videos

  • SEMICONDUCTOR ELECTRONICS (MATERIAL, DEVICES AND SIMPLE CIRUITS )

    AAKASH INSTITUTE|Exercise Assignment SECTION - D (Assertion & reason type Question)|10 Videos

Similar Questions

Explore conceptually related problems

A lens is placed between a source of light and a wall. It forms images of are A_(1) and A_(2) on the wall, for its two different positions, the area of the source of light is

A lens if placed between a source of light and a wall. It forms images of area A_(1) and A_(2) on the wall for its two different positions. The area of the source or light is

A lens is placed between the source of light and a wall. It forms images of area A_(1) and A_(2) on the wall for its two displaced positions. The area of source of light is

List out the difference between a point source and an extended source of light.

A source of light is located at a disatnce l = 90 cm from a screen. A thin converging lens provides the sharp image of the source when placed between the source of light and the screen at two positions. Determine the focal length o fthe lens if (a) the distance between the two positions of the lens is Delta l = 30 cm , (b) the transverse diamensions of the image at one position o fthe lens are eta = 4.0 greater than those at the pther position.

The internal surface of the walls of a sphere is specular (i.e. reflecting). The radius of the sphere is R = 36 cm . A point source S is placed at a distance R//2 from the centre of the sphere and sends light to the remote part of the sphere. Where will the image of the source be after two successive reflection from the remote and then the nearest wall of the sphere ? How wil the position of the image change if the source sends light to the nearest wall first ? Consider paraxial rays.

A source of light is placed in front of a screen. Intensity of light on the screen is I. Two Polaroids P_1 and P_2 are so placed in between the source of light and screen that the intensity of light on screen is I//2. P_2 should be rotated by an angle of (degrees) so that the intensity of light on the screen becomes (3I)/8

AAKASH INSTITUTE-RAY OPTICS AND OPTICAL INSTRUMENTS-ASSIGNMENT (SECTION - C)
  1. The refractive index of the material of a prism is sqrt(2) and the ang...

    Text Solution

    |

  2. Four lenses of focal length +15 cm , +20 cm, +150 cm and +250cm are av...

    Text Solution

    |

  3. Alens is placed between a source of light and a wall. It forms images ...

    Text Solution

    |

  4. If f(V) and f(R) are the focal lengths of a concex lens for violet and...

    Text Solution

    |

  5. A convex lens of focal length 80 cm and a concave lens of focal length...

    Text Solution

    |

  6. The focal lengths of a converging lens measured for violet, green and ...

    Text Solution

    |

  7. A luminous object is placed at a distance of 30 cm from the convex len...

    Text Solution

    |

  8. A plano-convex lens is made of refractive index 1.6. The radius of cur...

    Text Solution

    |

  9. For a plane convex lens (mu= 1.5) has radius of curvature 10 cm. It i...

    Text Solution

    |

  10. A bubble in glass slab (mu = 1.5) when viewed from one side appears at...

    Text Solution

    |

  11. A body is located on a wall. Its image of equal size is to be obtained...

    Text Solution

    |

  12. A convex lens is dipped in a liquid whose refractive index is equal to...

    Text Solution

    |

  13. Which of the following is incorrect?

    Text Solution

    |

  14. A double concave thin lens made out of glass (mu=1.5) have radii of cu...

    Text Solution

    |

  15. A convex lens forms a real image 16 mm long on a screen. If the lens i...

    Text Solution

    |

  16. A point object is moving with speed u(0) at a position somewhere betwe...

    Text Solution

    |

  17. The minimum magnifying power of an astronomial telescope is M. If the ...

    Text Solution

    |

  18. An object is placed in front of two convex lenses one by one at a dist...

    Text Solution

    |

  19. If R(1)andR(2) are the radii of curvature of the spherical surfaces of...

    Text Solution

    |

  20. The focal length of a thin lens in vacuum is f. If the material of the...

    Text Solution

    |