Recent content by shemy

Anyone?

Right, I need to find out the Radius of gyration of an object as it rolls down a ramp... So I've got the equation K=r square root((g.t^2 sin theta/ 2x) -1)) These are the numbers I have... Object A R = 0.004 g = 9.81 t = 16.45 theta = 5.31 x = 0.66 I got an answer of...

Right let's see! (1) 560 = Sigma0 + Ky(0.054)^-1/2 (2) 720 = Sigma0 + Ky(0.037)^-1/2 (3)160 = Ky(0.895) Ky=160/03895 = 178.77 560-(178.68)0.037^-1/2 = -368.91 -368.91+178.68*0.045^-1/2 = 473.95 720-(178.680.037^-1/2 = -208.91 -208.91+(178.68)0.037^-1/2 = 1137.82...

Yeh I'm using SigmaY = Sigma0 + Ky(D)-1/2 I guess you have to substitute in, but I'm not sure. Regards, Shemy

Right this is the question, Determine the yield stress for a metal with an average grain diameter of 0.045mm, if the yield stress for a metal changed from 650Nmm^-2 to 720Nmm^-2 when the average grain diameter decreases from 0.054mm to 0.037mm. I cannot figure this out, I've been trying...