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प्रश्न
The image of an extended object, placed perpendicular to the principal axis of a mirror, will be erect if
(a) the object and the image are both real
(b) the object and the image are both virtual
(c) the object is real but the image is virtual
(d) the object is virtual but the image is real.
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उत्तर
(c) the object is real but the image is virtual
(d) the object is virtual but the image is real
The virtual image of a real object and the real image of a virtual object are always erect.
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संबंधित प्रश्न
A 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. Give the location of the image and the magnification. Describe what happens as the needle is moved farther from the mirror.
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Can mirrors give rise to chromatic aberration?
A U-shaped wire is placed before a concave mirror having radius of curvature 20 cm as shown in figure. Find the total length of the image.
A converging lens of focal length 40 cm is kept in contact with a diverging lens of focal length 30 cm. Find the focal length of the combination .
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State how the focal length of a glass lens (Refractive Index 1.5) changes when it is completely immersed in:
(i) Water (Refractive Index 1.33)
(ii) A liquid (Refractive Index 1.65)
Answer the following question.
Three lenses of focal length +10 cm, —10 cm and +30 cm are arranged coaxially as in the figure given below. Find the position of the final image formed by the combination.
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A short object of length L is placed along the principal axis of a concave mirror away from focus. The object distance is u. If the mirror has a focal length f, what will be the length of the image? You may take L << |v – f|.
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= `k_1ln (K_2/b_("min")) b < b_("min")`
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Focal length of the concave mirror is ______.
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A converging lens has a focal length of 10 cm in air. It is made of a material with a refractive index of 1.6. If it is immersed in a liquid of refractive index 1.3, find its new focal length.
If an object is placed at a distance of 10 cm in front of a concave mirror of a focal length of 20 cm, the image formed will be ______.
