Question

An aluminium rod has a breaking strain 0.2%. The minimum cross-sectional area of the rod in $m^2$ in order to support a load of $10^4N$ is if Youngs modulus is $7 \times 10^9Nm^{-2}$

• A. $1.7\times 10^{-4}$
• B. $1.7\times 10^{-3}$
• C. $7.1\times 10^{-4}$
• D. $1.4\times 10^{-4}$

Answer 1

Answer: (C)

$7.1\times 10^{-4}$

Answer 2

Length to be double e = I, F = YA