1. in an atom, an electron and a proton are separated by a distance of 1 x 10-8m. a) find the force on the electron. b) assuming a circular orbit (which wouldn't happen, but we'll go with it). find the velocity of the electron.

In which of the following cases is work being done on an object? question 2 options: pulling a trailer up a hill carrying a box down a corridor suspending a heavy weight with a strong chain pushing against a locked door

What is the acceleration of a spaceship that is initially at rest and then speeds up to 220 m/s in 20 seconds

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.