Author: Physics Notebook
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What Are “Breaking Stress” And “Permanent Deformation”?
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Permanent Deformation: A permanent change occurs in a body when the elastic limit of the material of the body is crossed. It is called permanent deformation. For example, when a wire is stretched by a stretching force, then within the elastic limit the longitudinal strain is proportional to the stress, this means that it obeys…
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Calculate Work Done Per Unit Volume In A Strain. Or Calculate Strain Energy.
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Strain Energy: When a body is strained, internal forces due to the elastic property of the body are set up and hence work must be done by the applied force against the internal forces. The work is stored up within the body as potential energy which is known as the energy of strain or strain…
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Show That The Shear Strain Of A Cube Is Equivalent To Linear Strains Of Half The Magnitude In Mutually Perpendicular Direction.
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A shear is equivalent to a compression and an extension at right angle to each other: Let us consider a cube , having each side equal to with its lower face is fixed. Let us consider a tangential force is applied on the upper face , so that the cube is sheared to the new…
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Derive Stokes’ Law For The Viscosity Of A Small Sphere Falling Through A Viscous Liquid Using Method Of Dimension.
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Stokes’ Law: Let us consider, a spherical body of radius falls through a liquid of infinite extent having a coefficient of viscosity . After some time it attains a terminal velocity , then the resistive force on the spherical body due to viscous liquid becomes . This is known as Stokes’ law. Derivation of Stokes’…
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What Is Terminal Velocity?
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Terminal Velocity: When a body falls through a liquid or gas, it carries along with the layer of the fluid in contact and thus tends to produce a relative motion between the layers of the fluid. This relative motion is opposed by the force due to viscosity. The opposing force increases with the velocity of…
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Deduce An Expression For Effective Flow Resistance, When A Number Of Capillary Tubes Are Joined (i) In Series And (ii) In Parallel.
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According to Poiseuille’s formula, the rate of flow V of liquid through a capillary tube of length and radius is given by, , [Read In Detail] where, is the coefficient of viscosity of the liquid and is the pressure difference between the ends of the tube. Or, or, According to Ohm’s law for electricity, Potential…
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If A Number Of Capillary Tubes Are Adjoined (i) In Series, (ii) In Parallel, Derive The Expressions For The Rate Of Flow Of The Liquid Using Poiseuille’s Equation.
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(i) Flow through capillary tubes in series combination : According to Poiseuille’s equation, the rate of flow V of a liquid through a capillary tube of length and radius is given by, [Read In Detail] where, is the pressure difference across the end of the tube, is the coefficient of viscosity of the liquid. Let…
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Deduce An Expression For The Distribution Of Velocity Of A Fluid Flowing Through A Uniform Capillary Tube Of Circular Cross Section. What Is The Nature Of Velocity Of Profile?
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Distribution of velocity: Let us consider a horizontal capillary tube of length l and radius R as shown in the adjoining Fig. 1. Let us also consider that a liquid of coefficient of viscosity is moving in streamline flow in the tube along the axis of the tube. The velocity of the liquid is maximum…
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Explain Two Important Corrections To Poiseuille’s Formula.
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Corrections To Poiseuille’s Equation: Let us consider a horizontal tube of radius R and length l, If P is the pressure difference between the two ends of the tube then the total volume that passes through the tube in unit time is given by, [Read in detail] Where is the coefficient of viscosity of the…
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Derive Poiseuille’s Formula For The Flow Of A Liquid Through Narrow Horizontal Tube.
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Poiseuille’s Formula: Let us consider, a streamline motion of a liquid through a narrow tube, The streamlines are parallel to the axis of the tube and there is no radial flow of the liquid in the tube. The pressure over any given cross-section normal to the axis of the tube is constant. The pressure varies…