Check factor of safety for fatigue failure of h02 problem 4) after five years of continuous operation at crank speed 15 rpm with 99% reliability. use ½ x 1 inch 6061-t6511 (or 6061-t6) aluminum bar stock available from online metals. do not include stress concentrations for connections at a and b. use falt = 2200 lbf and fmean = 1800 lbf on each bar and use case 3) goodman failure.

The base of a 50-meter tower is at the origin; the base of a 50-meter tree is at (0, 50, 0). the ground is flat and the z-axis points upward. the following parametric equations describe the motion of six projectiles each launched at time t = 0 in seconds. (i) r (t) = (50 + t2)k (ii) r (t) = 2t2 j + 2t2k (iii) r (t) = 50 i + 50 j + (50 − t2)k (iv) r (t) = 2t j + (50 − t2)k (v) r (t) = (50 − 2t) i + 2t j + (50 − t)k (vi) r (t) = t i + t j + tk (a) which projectile is launched from the top of the tower and goes downward? at time t = , the projectile hits the ground at point (x, y, z) = . (b) which projectile hits the top of the tree?