an artist uses a ratio that compares the length and width of an average human face. Which type of model is this?

Acar tire contains 0.0380 m^3 3 of air at a pressure of 2.20 ×10^{5} 5 n/m^2 2 (about 32 psi). how much more internal energy does this gas have than the same volume has at normal atmospheric pressure, 1.01x10^5 5 pa?

Find the magnetic field a distance r from the center of a long wire that has radius a and carries a uniform current per unit area j in the positive z direction.

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.