Consider a flat plate of some metal alloy that is to be exposed to repeated tensile-compressive cycling in which the mean stress is 25 MPa. If the initial and critical surface crack lengths are 0.15 and 4.5 mm, respectively, and the values of m and A are 3.5 and 2 x 10^-14, respectively (for change in stress and a in m), estimate the maximum tensile stress to yield a fatigue life of 2.5 x 10^7 cycles. Assume the parameter Y has a value of 1.4, which is independent of crack length.

Ahot wire operates at a temperature of 200°c while the air temperature is 20°c. the hot wire element is a tungsten wire of 5 um diameter and 2 mm in length. plot using excel current, heat transfer and heat generated by the wire for air velocity varying from 1-10 m/s in steps of lm/s? matlab the sensor voltage output, resistance, or assume nu 0.989 re033pr13 take air properties at tr (200°c20°c)/2 = 110°c properties of tungsten: c 0.13 kj/kg.k 3 p 19250 kg/m k (thermal conductivity) = 174 w/m.k