Advertisements
Advertisements
प्रश्न
What is myopia?
उत्तर
Myopia (or) short-sightedness is a vision defect in which a person can see nearby objects clearly but cannot see the distant objects clearly beyond a certain point.
APPEARS IN
संबंधित प्रश्न
Answer the following question in detail.
What is the limitation in increasing the magnifying powers of a simple microscope?
Discuss about simple microscope and obtain the equations for magnification for near point focusing and normal focusing.
What is the near point focusing?
Why is oil-immersed objective preferred in a microscope?
What is astigmatism? What is its remedy?
Discuss about simple microscope and obtain the equations for magnification for near point focusing and normal focusing.
Discuss about astronomical telescope.
Mention different parts of the spectrometer.
Explain the experimental determination of the material of the prism using a spectrometer.
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
When a convex lens of 12.5 cm focal length is used as a magnifying glass, normal eye can see an object clearly at a distance of 25 cm. The magnifying power of the instrument is ____________.
If astronomical telescope of length 1.53 m has magnifying power of magnitude 50, the values of fo and fe are ____________.
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 magnifying power of a telescope is high if its objective and eyepiece have respectively ______.
An object viewed from a near point distance of 25 cm, using a microscopic lens with magnification '6', gives an unresolved image. A resolved image is observed at infinite distance with a total magnification double the earlier using an eyepiece along with the given lens and a tube of length 0.6 m, if the focal length of the eyepiece is equal to ______ cm.
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 ______.
In the adjoining figure, AB represents the incident ray, and BK is the reflected ray. If angle BCF = θ, then ∠BFP is given by ______.
