Answer to Question #196510 in Mechanics | Relativity for Abraham

Question

An iron rod 4m long & 0.5cm^2 in cross sectional area streches 1mm when a mass of 225kg is hong on it end. Extimate the stress and the strain experience by the iron rod?

Answer 1

Gives

Length(l )=4m

$$area(A)=0.5 cm^2=0.5\times10^{-4}m^2$$

∆l=1mm=$10^{-3}m$

Mass(M)=225kg

We know that

Stress $=\frac{F}{A}$

F=mg

$g=9.8m/sec^2$

$F=225\times9.8N=2205N$

$$Stress=\frac{2205}{0.5\times10^{-4}}=4.41\times10^7N/m^2$$

Strain$=\frac{∆l}{l}$

Put value

Strain=$\frac{1\times10^{-3}}{4}$ =$2.5\times10^{-4}$