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प्रश्न
How will you differentiate between a convex and a concave lens by looking at a printed page?
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उत्तर
On keeping the lens near a printed page, if the letters appear magnified, then the lens is convex, and if the letters appear diminished, then the lens is concave.
संबंधित प्रश्न
A ray of light incident on a lens parallel to its principal axis, after refraction passes through or appears to come from ______.
Study the diagram shown in Fig. 5.56
where is the object located?
State the condition of the following:
A lens has both its focal lengths equal.
Fig shows an object PQ placed on the principle axis of a lens L. The two foci of the kens are F1 and f2. The image formed by the lens is erect, Virtual and dimnished.
(i) Draw the outline ofthe lens L used and Named it.
(ii) Draw a ray of light starting from Q and passing through O. show the same ray after refraction by the lens.
(iii) Draw another ray from Q Which is incident parallel to the principle axis and show how it emerges after refraction from the lens.
(iv) Locate the final image formed.
In the following diagram the object and the image formed by the respective lenses are shown. Complete the ray diagram, and locate the focus. Find the focal length of the lens.
A lens forms the image of an object placed at a distance of 45 cm from it on a screen placed at a distance 90 cm on the other side of it. Name the kind of lens.
Name the subjective property of light related to its wavelength.
Complete the following diagram and state what happens to the ray of light after refraction through the lens.
