The emissivity of galvanized steel sheet, a common roofing material, is 0.13 at temperatures around 300 K, while its absorptivity for solar irradiation is 0.65. Determine the surface temperature, in °C, of a roof constructed of the material on a day when 350 W/m2, [infinity] 16°C, and 7 W/m2·K. Assume the bottom surface of the steel is insulated.

The force on a cutting tool are 2600n vertically downward and 2100 horizontal. determine the resultant force acting on the tool and the angle at which it acts.

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.

Ifa component is made of two or more materials with different modulus of elasticity (e), it is called a composite member and we calculate the factor·n". mention the formula for calculating n". also, ifn> 1, explain what will happen to the 1. transformed.gi) ifn 1, what will happen to the material when transformed material when