A biker travels at an average speed of 12 m/s along a 12 x 103 m straight segment of a bike path. How much time does the biker take to travel this segment?

Which of the following correctly describes the early view of catastrophism?

If steel is more dense that lake water, why can a boat float

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.