Acylindrical metal specimen having an original diameter of 11.88 mm and gauge length of 46.2 mm is pulled in tension until fracture occurs. the diameter at the point of fracture is 6.33 mm, and the fractured gauge length is 65.3 mm. calculate the ductility in terms of

(a) percent reduction in area (percent ra), and
(b) percent elongation (percent el).

Steel balls 12 mm in diameter are annealed by heating to 1150 k and then slowly cooled to 400 k in an air att 325 k and h -20 w/m2 k. assume the properties of the steel to be k- 40 w/m k, p 7800 kg/m3, and cp 600 j/kg k. a. determine whether lumped system method can be used to analyze this problem and if so why" b. determine the time required for the cooling process. c. determine the total amount of heat lost from each ball to the ambient air