If a low carbon steel A-36 must withstand 240 MPa of tensile stress, what is the maximum allowable length on an internal elliptical flaw whose radius of curvature at the flaw tip is 3 micrometer? Assume that the major axis of the elliptical flaw is perpendicular to the tensile loading axis and that the theoretical strength of a material is a tenth of its Youngs modulus.

Acompressor receives the shaft work to decrease the pressure of the fluid. a)- true b)- false

An air compression refrigeration system is to have an air pressure of 100 psia in the brine tank and an allowable air temperature increase of 60°f for standard vapor compression cycle temperatures of 77 f entering the expansion cylinder and 14 f entering the compression cylinder, calculate the coefficient of performance a. 2.5 b 3.3 c. 4.0 d. 5.0

Air at a pressure of 1atm and a temperature of 40 c is in parallel flow over the top surface of a flat plate that is heated to a uniform temperature of 120 c. the plate has a length of 0.40m (in the flow direction) and a width of 0.15m. the reynolds number based on the plate length is 50, 000. what is the rate of heat transfer from the plate to the air? if the free stream velocity of the air is doubled and the pressure is increased to 10 atm what is the rate of heat transfer?