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MechForge Guidebook · Mechanics of Materials
Theory
1.4 Normal Stress
Stress is the intensity of internal force on a specific plane (area) passing through a point.
σ = P / A
Practice
Problem 1.4-2
A solid steel rod of diameter d = 20 mm is subjected to a tensile load P = 45 kN. Calculate the normal stress in the member.
Verify
Detailed Solution
1 Identify knowns: P = 45 kN, d = 20 mm.
2 Area A = π(d/2)² = 314.16 mm².
3 σ = P/A = 143.2 MPa.
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