# Type 1. Problems on stresses and strain.

1. A steel rod 500mm long and 20mm10mm in cross-section is subjected to axial pull of 300 KN.If modulus of elasticity is 2105 N/mm2 .Calculate the elongation of the rod. Also calculate strain induced in the bar.

(Ans: 3.75mm,e=7.5E-3)

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2. A hollow cylinder 2 m long has an outside diameter of 50mm and inside diameter of 30mm. If the cylinder is carrying a load of 25 KN. FInd the stress in cylinder , also find deformation of the cylinder E=100 Gpa.

(Ans: Stress= 20.0 N/mm2 , Deformation= 0.4 mm )

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3. A load of 5KN is to be raised with the help of a steel wire. FInd the minimum diameter of wire if stress is not to exceed 100 MPa.

(Ans: d=7.98mm)

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4.In an experiment a steel specimen of 13mm diameter was found to elongate 0.2mm in a 200 mm gauge length when it was subjected to a force of 26.8 KN. If specimen was tested within elastic range, Calculate Young's modulus for the steel.

(Ans: E=201.9103 N/mm2 )

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5. A hollow cast iron column has internal diameter 200mm. What should be external diameter of the column, so that it could carry a load of 1600 KN without the stress exceeding 90 MPa.

(Ans: d=250.25 mm)

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6. A brass rod 1.5 m long and 20mm diameter was found to deform by 1.9mm under tensile load of 40KN. Calculate the modulus of elasticity.

(Ans:Modulus of elasticity=100 .51103 N/mm2 )

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7.A bar 500mm long and 22mm in diameter is elongated by 1.2mm under the effect of axial pull of 105 KN. Calculate stress,strain and modulus of elasticity..

(Ans:stress=276.22 N/mm2 ,strain=2.4 e-3, E=115.09 e3)

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8.A mild steel flat 75mm wide, 150mm thickness and 1.5 m long is subjected to pull of 45 KN. If elongation of flat is 0.6380mm. Find the young's modulus

(Ans:E=9.52e3 N/mm2 )

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9.An alloy bar 1m long and 200mm2 in cross section is subjected to compressive force of 20KN. If the modulus of elasticity is 100GPa. FInd decrease in the length of bar.

(Ans:1mm)