Consider the following states of biaxial stress: (1) = 30, = 0, (2) = 30, = −15, (3) = 30, = −30, (4) = 30, = 15, (5) pure shear, = 30. with the aid of a − plot, list these stress states in order of increasing likelihood of causing failure according to (a) the maximum-normal-stress theory, (b) the maximum-shear-stress theory, and (c) the maximum-distortion-energy theory. assume an arbitrary value of sy = 80 psi for the plot and calculate safety factors for each failure theory and stress state

Acommercial grade cubical freezer, 4 m on a side, has a composite wall consisting of an exterior sheet of 5.0-mm thick plain carbon steel (kst= 60.5 w/m k), an intermediate layer of 100-mm thick polyurethane insulation (kins 0.02 w/m k), and an inner sheet of 5.0- mm thick aluminium alloy (kal polyurethane insulation and both metallic sheets are each characterized by a thermal contact resistance of r 2.5 x 104 m2 k/w. (a) what is the steady-state cooling load that must be maintained by the refrigerator under conditions for which the outer and inner surface temperatures are 25°c and -5°c, respectively? (b) for power saving purpose, which wall material should be increased/reduced in. thickness in order to reduce 50% of the cooling load found in part (a)? redesign the thickness of the proposed material. 177 w/m-k). adhesive interfaces between the q=575.93 w

A21-tooth spur pinion mates with a 28-tooth gear. the diametral pitch is 3 teeth/in and the pressure angle is 20°, find the following values: the addendum, dedendum, circular pitch, tooth thickness, and base circle diameters.

Consider a 1.2 meter high and 2 meter wide glass window whose thickness is 6 mm and thermal conductivity is 0.78 w/m °c. the room temperature is maintained at 24 °c, while the outdoor temperature is -5 °c. the convective heat transfer coefficients on the inner and outer surfaces of the window are 10 w/m2 °c and 25 w/m2 °c respectively. (a) draw the thermal resistance network, etermine the steady rate of heat transfer t e glass window (c) determine the temperature of the inner surface of the window