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

Consider a large isothermal enclosure that is maintained at a uniform temperature of 2000 k. calculate the emissive power of the radiation that emerges from a small aperture on the enclosure surface. what is the wavelength ? , below which 10% of the emission is concentrated? what is the wavelength ? 2 above which 10% of the emission is concentrated? determine the wavelength at which maximum spectral emissive power occurs. what is the irradiation incident on a small object placed inside the enclosure?

Agas mixture consists of 8 kmol of h2 and 2 kmol of n2. determine the mass of each gas and the apparent gas constant of the mixture.

The proportional limit is always greater than the yield strength for a material. a)-trune b)- false