00:01
In this exercise, we have a nitrogen atom set up, and the electron is orbiting a proton, and it's moving in a circular orbit in the uniform circular motion.
00:16
Here, on the left -hand side, i wrote some quantities we must know to solve the exercise.
00:23
And what we have to find is what is the velocity of the electron's orbit.
00:30
So since the only force is a radial force, it's the electric force of the proton on the electron, we have a uniform circle motion.
00:41
And the expression for the uniform circle motion is, sorry, m, e, which is the mass of the electron, times v squared, which is the velocity of its orbit, over r, which is the, the radius of the orbit, and this must be equal to the electric force of the proton on the electron.
01:10
So it is equal to e squared, which is the modulum of the electric charge, since the electron and the proton has the same charge, times k, which is a quillum constant, over r squared.
01:31
So from here we can cancel out this r, and then we can isolate the velocity to find v is equal to k e squared over m .e and the square root of all of this...