Question

The stress produced in a wire of diameter 6 mm, when it is bent around a larger cylinder of diameter 2 m can be obtained as (Young's modulus of both wire and cylinder = 200 GPa )
The stress-strain curve of the material is given below .

• A. 600 MPa
• B. 300 MPa
• C. 100 MPa
• D. 200 MPa

Answer 1

The correct option is A 600 MPa

D = 2000 mm d = 6 mm

$R=\frac{D}{2}=1000mm$

y${}_{max}=\frac{d}{2}=3mm$

E = 200$\times {10}^3$ MPa

We have $f_{max}=\frac{E}{R}\times y_{max}$

=$\frac{200\times {10}^3}{1000}\times 3=600MPa$