Which of the following is true of mechanical waves? A. Mechanical waves are not sound waves.
B. Mechanical waves have repeating patterns.
C. Mechanical waves only move in one direction.
D. Mechanical waves disturb energy rather than matter.

Carbon is allowed to diffuse through a steel plate 15 mm thick. the concentrations of carbon at the two faces are 0.65 and 0.30 kg c/m^3 fe, which are maintained constant. if the preexponential and activation energy are 6.2 x 10-7 m2 /s and 80,000 j/mol, respectively, compute the temperature at which the diffusion flux is 1.43 x 10^-9 kg/m^2 -s.