Recent content by 3OPAH

You are correct. Neither dl nor R should have components along ez. Since the triangle lies in the x-y plane (z=0), dl should have components along ex and ey. Also, R should only have components along ex and ey because it's pointing from the location of dl , which is in the x-y plane, to the...

Hello, all. I have been working on the following problem and was wondering if someone could check my work and provide some valuable input: Here is my work: What do you guys think about my approach to this problem?

So we are given the initial velocity of v = aex + bey. The magnitude of the velocity vector has to be the same, but opposite in direction. So the necessary electric field is (with the magnetic flux density in there as well): E = -bB_0ex + aB_0ey correct?

If a charge experiences no net force, then its velocity is constant; the charge is either at rest (if its velocity is zero), or it moves in a straight line with constant speed. So the net force is zero.

My reasoning: The magnetic force on charge q is Fm = qv x B B does not change |v|. Therefore, |Fm| is constant at time t > 0 and Fm is always perpendicular to the direction of movement of charge q. Fm behaves as a centripetal force, and thus the charge moves along the circumference of a...

So here is my whole approach to the problem. What do you think, uart?

So electrostatic potential energy is qV and KE=1/2 mv^2. So we have: qV=1/2 mv^2 Solving for v, (velocity), v= Would that be the necessary calculation?

Ok, so E-field is constant which means that the plot for voltage vs position of electrons is linear inside the medium of the heated cathode. Then to calculate velocity of these electrons we simply equate the electrostatic potential energy and the kinetic energy of these electrons. Knowing that...

I understand that the voltage vs position is linear in a constant E-field, but why wouldn't the next step after calculating the current density, part c, be to calculate volume charge density? Then simply plug those two values into the equation for velocity of the electrons, u = J / \rho_v ?

Ok, so current density between the electrodes is very simple as you showed, but I am having trouble with the volume charge density calculation. I just need to figure out a way to calculate this volume charge density and then the velocity of the electrons is simply u = J / \rho_v . Any ideas, uart?

Hello all. I have been looking at this problem: I wrote three equations there, one for each part, which I think will help me solve each part; is my approach to the problem using those equations that you see there correct? I am just looking for some advice on where and how to start this problem...