Home
Class 12
PHYSICS
An observer looks at a distant tree of h...

An observer looks at a distant tree of height 10 m with a telescope of magnifying power of 20. To the observer the tree appears.:

A

20 times nearer

B

10 times taller

C

10 times nearer

D

20 times taller

Text Solution

Verified by Experts

The correct Answer is:
D

Angular magnification is 20
Promotional Banner

Topper's Solved these Questions

Similar Questions

Explore conceptually related problems

A small telescope has an objective lens of focal length 140cm and an eyepiece of focal length 5.0cm. What is the magnifying power of the telescope for viewing distant objects when (a) the telescope is in normal adjustment (i.e., when the final image is at infinity)? (b) the final image is formed at the least distance of distinct vision (25cm)?

An observer is at 2 m from an isotropic point source of light emitting 40 W power. What are the rms values of the electric and magnetic fields due to the source at the position of the observer ? [c=3xx10^(8)ms^(-1), epsilon_(0)=8.854xx10^(-12)C^(2)N^(-1)m^(-2)]

A thief is running away in a car with velocity of 20 m//s . A police jeep is following him, which is sighted by thief in his rear view mirror, which is a convex mirror of focal length 10 m. He observes that the image of jeep is moving towards him with a velocity of 1 cm//s . if the magnification of mirror for the jeep at that time is 1/10 . Find the actual speed of jeep, Assume the police's jeep is on the axis of the mirror.

The angle of elevation of a bird sitting on top of a tree as seen from the point at a distance of 20m from the base of the tree is 60^(@) . Then, the height of the tree is ……..m

An observer 1.7m tall, is 20 sqrt3m away from a tower. The angle of elevation of the top of the tower from the eyes of the observer is 30^(@) . Find the height of the tower.

A student measures the thickness of a human hair by looking at it through a microscope of magnification 100. He makes 20 observations and finds that the average width of the hair in the field of view of the microscope is 3.5 mm. What is the estimate on the thickness of hair ?

Two concentric circular coils X and Y of radii 16 cm and 10 cm, respectively, lie in the same vertical plane containing the north to south direction. Coil X has 20 turns and carries a current of 16 A, coil Y has 25 turns and carries a current of 18 A. The sense of the current in X is anticlockwise, and clockwise in Y, for an observer looking at the coils facing west. Give the magnitude and direction of the net magnetic field due to the coils at their centre.

An observer of height 1.8 m is 13.2 m away from a palm tree. The angle of elevation of the top of the tree from his eyes is 45^(@) What is the height of the palm tree?

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 6 cm 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 observer looks at a distant tree of height 10 m with a telescope of...

    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

    |