Doubts regarding Strength of material

Ankush Sharma

Ankush Sharma

@ankush-FCZUYR • Oct 23, 2024
hi friends...... i have few doubts regarding strength of material, so please can anyone give me solution for them........
1. why stress decreases from upper yield point to lower yield point in stress-strain curve?
2. when we draw shear force diagram and bending moment diagrams for beams, we usually see that when shear force is zero at that time bending moment is maximum, so my question is,why?
3. what is difference between moment of inertia and polar moment of inertia?

so friends if any one about these, then please reply here...... waiting.........
Like 0 Replies 2

Replies

Welcome, guest

Join CrazyEngineers to reply, ask questions, and participate in conversations.

Sign up Log in

CrazyEngineers powered by Jatra Community Platform

  • Ambarish Ganesh

    Ambarish Ganesh

    @ambarish-PQyoXg • Dec 19, 2012

    Consider this-
    BM and sf
    While M is the bending moment, the Shear Force F= Ra-W1-W2

    now, when F=0, Ra=W1+W2, which when substituted in M gives you the maximum bending moment, i.e. M=W1a+W2b.

    Ok, now let's see why this is maximum. See that the last equation contains no variable (no 'x'), so the rate of change of moment (dM/dx) must be zero for maximum bending moment right? 😀 Now as Moment is constant, differentiating it gives zero. Hence maximum bending moment.
    0
  • Ankush Sharma

    Ankush Sharma

    @ankush-FCZUYR • Dec 19, 2012

    The_Wise_Fool
    Consider this-
    BM and sf
    While M is the bending moment, the Shear Force F= Ra-W1-W2

    now, when F=0, Ra=W1+W2, which when substituted in M gives you the maximum bending moment, i.e. M=W1a+W2b.

    Ok, now let's see why this is maximum. See that the last equation contains no variable (no 'x'), so the rate of change of moment (dM/dx) must be zero for maximum bending moment right? 😀 Now as Moment is constant, differentiating it gives zero. Hence maximum bending moment.
    ok dear, right description................ but it is numerical one................ but, what if i suddenly ask this question from u?????? means if this question is asked in interview from u, then at that time what will u say?????? waiting...........
    0