## Physics: Principles with Applications (7th Edition)

a. Set the tensile strength of nylon (Table 9-2) equal to the applied stress on the string. tensile strength = $\frac{F_{max}}{A}$ $$F_{max}=(500\times 10^6 N/m^2)( \pi (0.0005 m)^2)= 393 N$$ b. To prevent breakage, use thicker strings with greater cross-sectional area. When the ball hits the strings, the tension increases, which may break the strings.