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  • 3) Why tensor? (2) Mechanics of materials

    Mathematics - Tensor Calculus  · 
      • When the engineer and the scientist want to analyze the stress for a declined or inclined surface, he/she would often use the Mohr’s circle. First, we start from the stress transformation diagram.

    useful image

    Fig. 1 - Stress Transformation Diagram
    1. Stress Transformation for 2-D case: Conventional Inducing Method

    By the...

  • 1) Stress and Strain - Stress

    Engineering - Mechanics of Materials  · 
    -1. Stress and Strain

    Stress means the force acting on the unit area, such as $\sigma\,=\,\frac{F}{A} [\frac{N}{m}]\,=\,[Pa]$ where $F\,:\,Force,\,A\,=\,Area$.

    Strain means the difference between the initial length and final length for compared to the initial length, such as $\epsilon\,=\,\frac{L_0\,-\,L_f}{L_0}$. where $L_0$ is initial length of a specimen of a certain material, and $L_f$ is final length of the specimen.

    The...