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प्रश्न
What is the remedy of myopia?
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उत्तर
A myopia eye is corrected by using a concave lens of focal length equal to the distance of the far point F from the eye.
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संबंधित प्रश्न
Define and describe the magnifying power of an optical instrument.
Answer the following question in detail.
How does magnifying power differ from linear or lateral magnification?
Answer the following question in detail.
Derive an expression for the magnifying power of a simple microscope. Obtain its minimum and maximum values in terms of its focal length.
Answer the following question in detail.
Obtain the expressions for magnifying power and the length of an astronomical telescope under normal adjustments.
Answer the following question in detail.
What is the limitation in increasing the magnifying powers of the astronomical telescope?
Discuss about simple microscope and obtain the equations for magnification for near point focusing and normal focusing.
Why is oil-immersed objective preferred in a microscope?
What is the use of collimator in a spectrmeter?
What is hypermetropia?
What is presbyopia?
Discuss about simple microscope and obtain the equations for magnification for near point focusing and normal focusing.
Mention different parts of the spectrometer.
Explain the preliminary adjustments of the spectrometer.
Explain the experimental determination of the material of the prism using a spectrometer.
A compound microscope has a magnification of 30. The focal length of eye piece is 5 cm. Assuming the final image to be at least distance of distinct vision, find the magnification produced by the objective.
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.
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.
In the adjoining figure, AB represents the incident ray, and BK is the reflected ray. If angle BCF = θ, then ∠BFP is given by ______.
A camera objective has an aperture diameter of d. If the aperture is reduced to diameter d/2, the exposure time under identical conditions of light should be made ______.
