Question $3($i$)$ A uniform circular section beam, length L$,$ diameter d$,$ extends an amount x under a tensile pull P$.$ Use Macaulay$$s method to derive an appropriate expression for deflection of the beam, which when further developed shows that the maximum deflection of the beam, simply supported at its ends and carrying a central point load W$,$ is given by $=$ WxL$2/3$Pd$217$ marks $($ii$)$ What is the ratio $/$x if L $=100$d and the maximum bending stress due to W is equal to the tensile stress due to the pull P$?$