Advertisements
Advertisements
Question
Discuss about astronomical telescope.
Advertisements
Solution
- An astronomical telescope is used to get the magnification of distant astronomical objects like stars, planets, moon, etc. the image formed by an astronomical telescope will be inverted.
- It has an objective of long focal length and a much larger aperture than the eyepiece.
- Light from a distant object enters the objective and a real image is formed in the tube at its second focal point.
- The eyepiece magnifies this image producing a final inverted image.
Astronomical telescope - The magnification m is the ratio of the angle β subtended at the eye by the final image to the angle ∞ which the object subtends at the lens or the eye.
m = `β/α`
From the diagram,
m = `("h"//"f"_"e")/("h"//"f"_0)`
m = `"f"_0/"f"_"e"`
The length of the telescope is approximate, L = f0 +fe
APPEARS IN
RELATED QUESTIONS
Answer the following question in detail.
What is a terrestrial telescope and an astronomical telescope?
Answer the following question in detail.
What is the limitation in increasing the magnifying powers of a compound microscope?
Answer the following question in detail.
What is the limitation in increasing the magnifying powers of the astronomical telescope?
What is the near point focusing?
What are the advantages and disadvantages of using a reflecting telescope?
What is the remedy of myopia?
What is the remedy of hypermetropia?
What is presbyopia?
Discuss about simple microscope and obtain the equations for magnification for near point focusing and normal focusing.
Obtain the equation for resolving the power of the microscope.
Explain the preliminary adjustments of the spectrometer.
A compound microscope has a magnifying power of 100 when the image is formed at infinity. The objective has a focal length of 0.5 cm and the tube length is 6.5 cm. What is the focal length of the eyepiece.
The near point and the far point for a person are 50 cm and 500 cm, respectively. Calculate the power of the lens the person should wear to read a book held in hand at 25 cm. What maximum distance is clearly visible for the person with this lens on the eye?
There are four convex lenses L1, L2, L3 and L4 of focal length 2, 4, 6 and 8 cm, respectively. Two of these lenses from a telescope of length 10 cm and magnifying power 4. The objective and eye lenses are respectively
The magnifying power of a telescope is nine. When it is adjusted for parallel rays, the distance between the objective and eyepiece is 20 cm. The focal length of objective and eyepiece are respectively.
The speed of light in media 'A' and 'B' are 2.0 × 1010 cm/s and 1.5 × 1010 cm/s respectively. A ray of light enters from medium B to A at an incident angle 'θ'. If the ray suffers total internal reflection, then ______.
Magnification produced by astronomical telescope for normal adjustment is 10 and length of telescope is 1.1 m. The magnification when the image is formed at least distance of distinct vision (D = 25 cm) is ______.
The image formed by an objective of a compound microscope is ______.
In the adjoining figure, AB represents the incident ray, and BK is the reflected ray. If angle BCF = θ, then ∠BFP is given by ______.
