Which situation results in the most attraction between two magnets? A. the north pole of one magnet is far away from the north pole of the other magnet.
B. the South pole of one magnet is near the South pole of the other magnet.
C. the north pole of one magnet is near the South pole of the other magnet.
D. The north pole of one magnet is far away from the South pole of the other magnet.

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.