Q. A steel bar 10 cm broad and 8 mm thick is subjected to bending moment. The radius of the neutral surface is 100 cm. Found out the maximum and minimum bending stress in beam.
Sol.: Let for steel bar E = 2 × 10^{5} N/mm^{2}
y^{max} = 4mm
R = 1000mm
σ_{max} = E.y_{max} /R = (2 × 10^{5} × 4 )/1000