The electric force between two charged particles is 0.18 newtons. If the
distance between them is increased by a factor of 3.0, what will the new
electric force be

Which is not true about oxygen-17 and oxygen-18?

Find v(t), given acceleration a(t)=7j and initial velocity v(0)=k

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.