When you look at a process using the point of view of energy as opposed to the point of view of forces, typically?
a. you use the exact same equations.
b. you predominantly use vector quantities.
c. you use more math, but it's less abstract.
d. you use less math, but it's more abstract.

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.

Arigid tank is divided into two equal parts by a partition. one part of the tank contains 3 kg of compressed liquid water at 400 kpa and 60°c while the other part is evacuated. the partition is now removed, and the water expands to fill the entire tank. determine the entropy change of water during this process, if the final pressure in the tank is 40 kpa. use steam tables.

Write a hypothesis about the effect of increasing resistance on the current in the circuit. use theformat and be sure to answer the lesson question. “how do changes in voltage or resistance affect current in an electric circuit? ”