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प्रश्न
Define magnifying power of a telescope. Write its expression.
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उत्तर
Magnifying power of a telescope is defined as the ratio of the angle subtended at the eye by the image formed at the least distance of distinct vision to the angle subtended at the eye by the object lying at infinity, when seen directly.
The formula for magnifying power is,
Magnifiying power,`M = - f_0/f_e (1 + f_e/D)`
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संबंधित प्रश्न
Why should the objective of a telescope have large focal length and large aperture? Justify your answer.
With regard to an astronomical telescope of refracting type~ state how you will increase its:
1) magnifying power
2) resolving power
State the condition under which a large magnification can be achieved in an astronomical telescope.
Draw a ray diagram showing the image formation of a distant object by a refracting telescope ?
Write two important limitations of a refracting telescope over a reflecting-type telescope.
Define its magnifying power and write the expression for it?
A small telescope has an objective lens of focal length 150 cm and an eye piece of focal length 5 cm. If this telescope is used to view a 100 m high tower 3 km away, find the height of the final image when it is formed 25 cm away from the eye piece.
How is the working of a telescope different from that of a microscope?
A Galilean telescope is 27 cm long when focussed to form an image at infinity. If the objective has a focal length of 30 cm, what is the focal length of the eyepiece?
Assertion: An astronomical telescope has an objective lens having large focal length.
Reason: Magnifying power of an astronomical telescope varies directly with focal length of the objective lens.
