Lightweight aggregate concrete slab of density rho = 1500 kg/m3 consists of a solid, stone mix concrete matrix within which are small spherical pockets of air. Determine the effective thermal conductivity of the slab. Evaluate properties at T=300 K

Amass of 1.5 kg of air at 120 kpa and 24°c is contained in a gas-tight, frictionless piston-cylinder device. the air is now compressed to a final pressure of 720 kpa. during the process, heat is transferred from the air such that the temperature inside the cylinder remains constant. calculate the boundary work input during this process.

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

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