Design a double angle section for the lower chord of the roof truss depicted below. Allow for a double row of bolt holes in the larger leg. The smaller leg of the double angle used for the lower chord does not have bolts. Finally, assume no fewer than 3 bolts per line in the direction of the load. Use ASD.

The temperature of air decreases as it is compressed by an adiabatic compressor. a)- true b)- false

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.

Determine the damped natural frequencies and the steady state response of a decoupled damped forced two degrees of freedom system. 10ä1 + 2q1 20q1 10 cos t; 10q2 +4q2 + 40q2 10 cos t