| Previous Year Questions of March Examinations from 2010 to 2020 |
| Chapter Name: MECHANICAL PROPERTIES OF SOLIDS |
Match the following
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| Elasticity is the property of matter that is characterized by atomic packing. For an elastic solid, stress applied is directly proportional to the strain produced in it. The stress versus strain graph for three materials A, B and C is shown. a) Which is more elastic A, B or C? Justify your answer. b) If the bulk modulus of water is 2 x 109 Nm-2 , find its compressibility. c) Why are girders for supporting roofs formed in the shape of I? |
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When a mass is suspended on a metallic wire, the length of the wire increases slightly. a) Name and the state law that relates to the restring force developed in the wire and its deformation. b) Draw the stress – strain graph of a loading wire. Mark the following points: i. Elastic limit ii. Fracture point iii. Plastic region iv. Elastic region c) If the young’s moduli of iron and glass are 190 x10 9 Nm -2 and 65 x 10 9 Nm -2 respectively. Which is more elastic? Justify your answer. |
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Velocity of sound depends on density (ρ) and modulus of elasticity (E). (the dimensional formula of E is ML -1 T -2 ). a) State the principle of homogeneity b) Using the above principle, arrive at an expression for the velocity of sound. (Take K=1). |
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Hooke’s law states that stress α strain. a) What is the necessary condition for the above law to be valid? b) Explain with the help of a graph, the relation between stress and strain for a given solid material under increasing tensile stress. |
| The graph shows how the force applied to a metal wire is related to the extent ion of the wire. a) Write the letter that corresponds to: i) Elastic limit ii) Fracture point b) The wire has an unstretched length of 2.40 m and an area of cross section of 3.90 x 10–7 m2 . Determine the Young’s modulus Y of the material. |
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A rubber band can be pulled to several items its original length. a) Draw the stress-strain graph of a rubber band. b) Rope of cranes is made of a number of thin wires braided together. Why? |
| A rigid is a body with a perfectly unchanging shape under the influence of an external force. a) What you mean by the centre of mass of a rigid body? b) A rigid beam of length L, breadth b and depth d is supported near its ends as shown in the figure. A load W is suspended at its centre of mass. Write the expression for the amount of sagging. |
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| The stress-strain graph for wires of two materials A and B are given below. a) Which material is more ductile? b) When a spring balances are continuously used for long time, they show wrong reading. Explain why |
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| Asteel rod has a radius of 10 mm and a length of 1.0 m. A 100 kN force stretches it along its length. Caculate the elongation of the steel rod. [Youngs modulus of steel is 2.0 x 1011 N/m2 ] |
| A metal cube of side 10 cm is subjected to a shear stress 104 N/m2. Calculate the rigidity modulus, if the top of the cube is displaced by 0.05 cm with respect to its bottom |
| A typical stress-strain graph of a metallic wire is shown a) Write the name of the point B labelled in the graph b) For materials like copper the points D and E are (close / far apart) |
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| Figure shows the strain-stress curve for a material (a) What is the Young"s modulus of the material (b) Young"s modulus of Aluminium is 70 x 109 Nm-2 and that of copper is 120 x109 Nm-2 . Same strain is to be produced on an Aluminium wire and a copper wire of equal cross section. Which wire requires more force? |
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Young"s Modulus of rubber is a) greater than that of steel b) less than that of steel c) equal to that of steel |
| Beam of different cross-sectional shapes are shown in figure. Why the beam B is using in the construction of bridges ? |
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| State Hooke’s Law |
| A typical stress-strain curve for a metal is given below. What is denoted by the points A and B ? |
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