An opaque surface, 2 m by 2 m, is maintained at 400 K and is exposed to irradiation with G = 1200 W/m2. The irradiation has the spectral distribution of a blackbody at 4000 K. The surface is diffuse and its spectral absorptivity is ai = 0.3 = 0.5 = 0.75 = 0.9 0< < 0.5 um 0.5 um << 1.0 um 1.0 um < 2.0 um > 2.0 um Determine the absorbed radiation, the emissive power, and the net radiation heat transfer.

During a steady flow process, the change of energy with respect to time is zero. a)- true b)- false

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.

The flow rate of air through a through a pipe is 0.02 m5/s. a pitot static tube is placed in the flow. the radius of the pitot static tube is 1 mm. assuming the flow to be steady and the air to be at 300k, calculate the difference in total and static pressure if the diameter of the pipe is: (a) d 0.1 m d 0.05 m (c) d 0.01 m