Questions
Question 1
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A \(1800\,\mathrm{N}\) tensile force acts on cross-sectional area \(6.0\times10^{-4}\,\mathrm{m^2}\). Find the normal stress.
Question 2
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A \(1.8\,\mathrm{m}\) tie extends by \(0.72\,\mathrm{mm}\). Find the tensile strain.
Question 3
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A compressive force of \(900\,\mathrm{N}\) acts on area \(3.0\times10^{-4}\,\mathrm{m^2}\). Find the stress magnitude and state whether it is tensile or compressive.
Question 4
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A rod has length \(1.5\,\mathrm{m}\) and tensile strain \(4.0\times10^{-4}\). Find its extension.
Question 5
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A shear force of \(600\,\mathrm{N}\) acts on area \(2.0\times10^{-3}\,\mathrm{m^2}\). Find the shear stress.
Question 6
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A rectangular block of height \(0.20\,\mathrm{m}\) is sheared sideways by \(0.50\,\mathrm{mm}\). Find the shear strain.
Question 7
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Two rods carry the same tensile force. Rod A has twice the cross-sectional area of rod B. Compare their normal stresses and explain the physical meaning.
Question 8
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A circular wire of diameter \(1.2\,\mathrm{mm}\) carries \(150\,\mathrm{N}\). Find the tensile stress and compare it with a yield stress of \(180\,\mathrm{MPa}\).
Question 9
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A vertical cable supports a load \(P\). The cable has two equal-length sections in series: the upper section has area \(2A\), the lower section has area \(A\). Derive the stress in each section, state the assumption about internal force, and interpret which section controls yielding.
Question 10
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A tensile member has cross-sectional area \(A(x)=A_0(1+\alpha x/L)\) for \(0\le x\le L\), with \(\alpha>0\), and carries axial force \(F\). Derive \(\sigma(x)\), find the maximum stress, and give the symbolic no-yield condition for yield stress \(\sigma_y\). State assumptions and interpret the role of \(\alpha\).