11. Explain with the help of a diagram, why a pencil partly immersed in water appears to be bent at the water surface. [Delhi] -Chemistry-10

11. Explain with the help of a diagram, why a pencil partly immersed in water appears to be bent at the water surface. [Delhi] -Chemistry-10
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Answer. Light from different points on the pencil, immersed in water refracts and appears to come from a point above the original position.
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When a pencil is partly immersed in water in a slanting position, the immersed portion appears (a) bent towards the bottom (b) bent towards the water surface (c) bent in a zigzag manner (d) curved downward

Description : When a pencil is partly immersed in water in a slanting position, the immersed portion appears (a) bent towards the bottom (b) bent towards the water surface (c) bent in a zigzag manner (d) curved downward

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Description : 5. The refractive indices of four media A, B, C and D are given in the following table: -Chemistry-10

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Description : 2. An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens. [All India] -Chemistry-10

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When a pencil is dipped in glass of water it appears bent near the surface of water due to ______ of light. a) refraction b)reflection c)bouncing back of light d)none

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A spherical ball made of steel when dropped in mercury container will – (1) sink in mercury (2) will be on the surface of mercury (3) will be partly immersed mercury (4) will dissolve in mercury

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Centre of pressure of a plane surface of arbitrary shape immersed vertically in a static mass of fluid(A) Lies above the centroid of the plane surface(B) Is independent of the specific weight of the fluid(C) Is different for different fluids(D) Is at the centroid of the plane surface

Description : Centre of pressure of a plane surface of arbitrary shape immersed vertically in a static mass of fluid (A) Lies above the centroid of the plane surface (B) Is independent of the specific weight of the fluid (C) Is different for different fluids (D) Is at the centroid of the plane surface

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The total pressure on a horizontally immersed surface is (where w = Specific weight of the liquid, A = Area of the immersed surface, and x = Depth of the centre of gravity of the immersed surface from the liquid surface) (A) wA (B) wx (C) wAx (D) wA/x

Description : The total pressure on a horizontally immersed surface is (where w = Specific weight of the liquid, A = Area of the immersed surface, and x = Depth of the centre of gravity of the immersed surface from the liquid surface) (A) wA (B) wx (C) wAx (D) wA/x

Last Answer : Answer: Option C

The intensity of pressure on an immersed surface __________ with the increase in depth. (A) Does not change (B) Increases (C) Decreases (D) None of these

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The depth of centre of pressure (h) for a vertically immersed surface from the liquid surface is given by (where IG = Moment of inertia of the immersed surface about horizontal axis through its centre of gravity, A = Area of immersed surface, and x = Depth of centre of gravity of the immersed surface from the liquid surface) (A) (IG/ ) - (B) (IG/ ) - (C) ( /IG) + (D) (IG/ ) +

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Jam nut is a locking device in which (A) A smaller nut is tightened against main nut creating friction at the contacting surface (B) A split pin is passed through diametrically opposite slots in nut and a hole in bolt and the two ends of split pin are separated and bent back on nut (C) A slot is cut in the middle of nut along the length and a cap screw is provided to tighten the two parts of nut separated by slot (D) An elastic piece is tightened in the nut by a setscrew

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Last Answer : (A) A smaller nut is tightened against main nut creating friction at the contacting surface

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Last Answer : (B) A split pin is passed through diametrically opposite slots in nut and a hole in bolt and the two ends of split pin are separated and bent back on nut

When light falls on shiny surface it gets __________ . a) refracted b)reflected c)bent d)nothing happens

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Which of the following terms best describes the reason that light is refracted at different angles? ∙ A. Photon energy changes with wavelength ∙ B. Light is refracted as a function of surface smoothness ∙ C. The angle is determined partly by a and b ∙ D. The angle is determined by the index of the materials

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Last Answer : ∙ D. The angle is determined by the index of the materials

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Description : A coupler which consists of a series of lenses and a partly reflective surface ∙ a. Beam-splitting coupler ∙ b. Reflective star coupler ∙ c. Fused coupler ∙ d. None of these

Last Answer : ∙ a. Beam-splitting coupler