Question

The maximum bending stress induced in a steel wire of modulus of elasticity 200 kN/$m{m}^2$ and diameter 1 mm when wound on a drum of diameter 1 m is approximately equal to

• A. $50N/m{m}^2$
• B. $100N/m{m}^2$
• C. $200N/m{m}^2$
• D. $400N/m{m}^2$

Answer 1

The correct option is C $200N/m{m}^2$

$\frac{M}{I}=\frac{f}{y}=\frac{E}{R}$

$\Rightarrow f=\frac{Ey}{R}=\frac{200\times {10}^{3}N/m{m}^2\times 0.5mm}{500mm}$

$=200N/m{m}^2$