\({m_1} = (m + m) = 2m\) , \({m_2} = m\)
\(\therefore \) \(T\) \( = \frac{{m.\,2m\,.g}}{{m + 2m}}\)\( = \frac{2}{3}mg\)
\(\therefore \,\) પ્રતિબળ \( = \frac{T}{a} = \frac{2}{{3a}}mg\)
\({\rm{Strain}} = \frac{{{\rm{Stress}}}}{{{\rm{Young's modulus}}}} = \frac{2}{3}\frac{{mg}}{{aY}}\)