Lorentz force Definition and 202 Threads

It is known that in a current carrying wire, exposed to a magnetic field, the wire will experience a force equal to the product of the field, the current and the length of the wire (where the direction of the force is orthogonal to both the field and the direction along the length of the beam)...

I have a few questions about this effect. If I have some semiconductor of N type in which I have electrical field in x direction, and magnetic field in z direction \vec{E}=E\vec{e}_x \vec{B}=B\vec{e}_z Then Lorence force is in the -y direction because in N type of semiconductor n>>p so...

The lorentz foce has been bothering me. Becouse it seems to sugest an abosolute velocity. Say you have tw parrellel wires, with equal current running in the same direction. According to Lorrentz force, they attract. Now, the two wires are plasma. The curents are running side by side, at...

Homework Statement Show that the 4-force law: F_u=q/c E_{uv}U^v leads to the usual Lorentz force law. Homework Equations F = E + v x B. The Attempt at a Solution What's U?

I'm wondering what happens (or if it makes sense) if in the formula \mathbf{F} = q (\mathbf{E} + \mathbf{v} \times \mathbf{B}) we replace v by Lorentz factor, that is \frac{1}{\sqrt{1-\frac{v^2}{c^2}}}. I realize that in the new formula I'm cross-producting a scalar with a vector, but I could...

This is doing my nut in. I'm looking at causes of errors in a rotating gradiometer. It uses a loop of superconductor formed so that the current in the loop is proportional to the gradient of the magnetic field threading the loop. I think that an error current will arise due to the Lorentz...

Reading Jackson this morning, where it was stated that the Lorentz force equations: \frac{dU^\alpha}{d\tau} = \frac{e}{mc} F^{\alpha\beta} U_\beta are sufficient to describe the motion of a charged particle in an external field, neglecting the effects of radiation. That radiation...

\textbf{L} \ = \ q\left( \textbf{v \ x \ B} \right) L, v, and B are vectors, and B represents magnetic induction. if \textbf{v} \ = \widehat{x}, then \textbf{v x B} = \widehat{x} \ \textbf{x B} What is this quantity, \widehat{x} \ \textbf{x B}, geometrically?

I am trying to bridge a gap between Maxwell equations and Lorentz force. I know that they are not independent and in theory, one could be derived from the other but I cannot see that. More physics oriented people prefer the Lorentz force because it describes the effect of B and E as a final...

For my Final Project for my AP Physics class is a rail gun. But I am having trouble getting it to fire anything or even move it. I have no trouble charging the bank but when it is discharged into the rails the projectile doesn't move. I am using 11, 330v disposable camera capacitors in...

ok, the lorentz force equation is F=q(E+v x B) and Newton's 2nd law is F=ma. I need to combine the two to show that ma.v=qE.V I don't really know what to do first here... i can see the simple substitution so that ma=qE+q(v x B) but beyond that...do u change the a to dv/dt. Any type of help...

Homework Statement Given: a quarter-circle of wire (radius r=0.75m) in a uniform 1.7T magnetic field carrying a current of 3.5A (see diagram) Find: The force on the wire. Note: the connecting wires delivering the current to the quarter circle are parallel to the magnetic field and...

Homework Statement In frame S, two identical point charges q move abreast along lines parallel to the x-axis, a distance r apart and with speed v. Determine the force in S that each exerts on the other: a) using the lorentz force in conjunction with the field of a moving charged particle...

Hello, The Lorentz force equation, F = q (E + v x B), is a complete description of the force on bodies arising from Magnetism and Electricity, right? So somehow it must be possible to get from the magnetism that exists in materials (like in a magnet) to this equation. I don't see how the...

Homework Statement Ok here it goes... A stream of electrons, each with speed u = 5.9 x 10^6 m s^-1 and traveling along the x-axis in the positive x-direction enters a region pervaded by a uniform magnitic field B. The electrons the describe a circle with raidus R in the horizontal xy-plane...

HI all: I have one confused question. a infinitely long wire carrying constant direct current is placed in the space. One particle with charge q and velocity v is moving in the magnetic field which is created by current-carrying wire. We know in the lab frame. particle will accelerate in this...

F= q(v x B) B= v x q*k*d/r^2 It is a basic physics knowledge magnetic field forms around moving charge, it tell us magnetic field is zero when charge is not moving and strength of magnetic field increases as velocity increases, right? Magnetic potential vector field increases with "absolute...

Does the lorentz force occur at the atomic level?

I am trying to calculate the strength of the magnetic field ( in teslas ) that would be needed to deflect cosmic rays going about 99% the speed of light. using the lorents force http://en.wikipedia.org/wiki/Lorentz_force I replaced force with mass times acceleration I canceled...

The Lorentz Force and Maxwell's equations derived from Klein Gordon's equation . http://www.physics-quest.org/Book_Lorentz_force_from_Klein_Gordon.pdfI posted several new chapters of my book lately, mostly involving the Klein Gordon equation. This chapter shows how the Lorentz Force has a...

Hi, I am trying to use DSolve in Mathematica 6.0.1.0, in order to find equations of motion (x[t], y[t]) from second-order differential equations. I have looked through much documentation, and attempted numerous codes to figure this out, but get many errors or the same answer every time. This...

From Lorentz force law, F = q (v х B) = q v B sin θ F = q v B [For θ = 90] W = F * d = F d cos θ w = 0 [For θ = 90] How come we have a force but no work done?

If I use the following Lagrangian: \mathcal{L} = \frac{1}{2} m v^2 + e A \cdot v/c = \frac{1}{2} m \dot{x}_\mu \dot{x}^\mu + e A_\nu \dot{x}^\nu /c I can arrive at the Lorentz force equation in tensor form: m \ddot{x}_\mu &= (q/c) F_{\mu\beta} \dot{x}^\beta details offline...

I've been slowly self studying Lagrangian topics, and have gotten to Noether's theorem. I've tried application of a Lorentz boost to all the terms in the Lorentz force Lagrangian (which is invariant with respect to boost since it has only four vector dot products). Then using Noether's...

Basic electrostatics (as I've seen it presented) usually starts off with an implicit \mathbf{F} = q q_2 \hat{\mathbf{r}}/r^2 = q \mathbf{E} definition of the electric field. Then with a limiting volume argument, you can then show that this can be expressed div \mathbf{E} = \rho. Eventually one...

Hi! I would really appreciate some help on the relativistic Lorentz force as applied to a charged particle; it's my first post on this site btw. Thanks in advance ;) QUESTIONS (a) A charged particle with total energy E0 is injected into a region of space containing a uniform...

I need to know the correct expression for the Lorentz force on a relativistic particle in an EM field, in cgs units, in terms of vector potential A and scalar potential phi, to prove that a given Lagrangian produces the correct equations of motion. I don't need it in covariant form with tensors...

Hi, everyone. In a course on superconducting materials, my lecturer has suggested that in a Type I(one) superconductor, any normalconducting region containing trapped magnetic flux will feel a Lorentz force per unit volume F_L = J \times B, where J is the transport current density (vector!)...

I was wonder if anybody might know how to solve this (this is not a homework problem, btw). The Lorentz Force is given by: \vec{F}=q(\vec{E}+\vec{v}\times\vec{B}) Now afer working that out, I get three differential equations: \frac{dv_x}{dt}=\frac{q}{m}(E_x+v_yB_z-v_zB_y)...

[SOLVED] Lorentz Force Law Problem Problem and known data: 34.6 An electron travels with velocity 4.9 X 10^6 m/s in the i direction, through a point in space where the magnetic field is .111 T in the j direction. The force on the electron at this point is F=(9.5 x 10^-14 i - 9.5 x 10^-14...

[SOLVED] lorentz force Homework Statement Say you a magnetic field perpendicular to the direction of a current. If you consider the current as electrons moving forward then the Lorentz force on the electrons points up (say). But if you consider the current is a lot of positive charge...

Why does it, and these other laws/effects work? Can anyone explain why the Right Hand Rule works, on a quantum scale? Lorentz Force law http://www.ee.byu.edu/em/lorentz.htm Right hand rule http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magfor.html The hall effect...

I have a question regarding electrons in an electric and magnetic field and I need to apply Lorentz force law to find the direction in which the electric field is pointing. Would someone be good enough to explain how the right hand rule applies in this situation? I think I might be getting...

Assuming the Lorentz force law and also that in the rest frame of the particle the 3 acceleration is zero, we need to explain why the following equations hold: E.v = 0 and E + v.B = 0 where v is the velocity. I think this is because g(A,A) = -a squared is invariant. Therefore if a=0, I...

An electron is moving with a speed of V when it enters an electric field generated by two equally but oppositely charged parallel plates. The electron passes through the field without being deflected. How can this be? I was thinking that the electrons electric field would cancel out with...

Homework Statement The motion of a charged particle P, observed in an inertial frame S. It is found that P moves with constant velocity v through a region of space where there is a uniform electric field E and a uniform magnetic field B. The speed v = |v|and the field magnitudes E = |E| and...

Homework Statement The motion of a charged particle P, observed in an inertial frame S. It is found that P moves with constant velocity v through a region of space where there is a uniform electric field E and a uniform magnetic field B. The speed v = |v|and the field magnitudes E = |E| and...

Was wondering if anyone is familiar with lorenzt force? Here is the problems whatever help you can give that would be great thank you in advance. Does anyone know a good site to practice these types of problems Homework Statement An electron is moving initially in the +x direction in a...

Homework Statement A particle of charge q starts from rest at the origin of coordinates in a region where there is a uniform electric field of strenth E parallel to the x-axis, and a uniform magnetic field B parallel to the z-axis. Find the equations of motion, and solve them to show that...

* implies time derivative, _i and _j are indices. Homework Statement Consider a Particle of mass m and charge q acted on by electric and magnetic fields E(x,t) and B(x,t). these fields can be described in therms of the scalar and vector potentials PHI(x,t) and A(x,t) for which E= -...

I read somewhere that the whole of magnetism, and in particular the lorentz force, can be found merely by applying the lorentz transformation to transform the coordinates of the electric field of a charged particle from the frame in which the particle is at rest to a frame in which the particle...

A singly charged lithium ion is accelerated by an electric field E=10i V/m applied between two plates ten centimeters apart. After passing through a small hole in the negative plate, the ion enters a region of space where there is a magnetic field B=5j mT. The ion moves in a circular path. What...

\mathbf \nabla \times (\mathbf E + \mathbf v \times \mathbf B) pluggin stuff from Maxwell equations = -\frac{\partial B}{\partial t} + \mathbf v (\mathbf \nabla \cdot B) - \mathbf B (\mathbf \nabla \cdot v) Since \frac{\partial}{\partial t}(\mathbf \nabla \cdot \mathbf r) = 0 it's =...

In a railgun the lorentz force causes an object to be propelled in a direction because of an electromagnetic force caused by running a current through the "rails". How come you can use aluminium or another such non-magnetic metal as both rails and armature? Surely only a magentic metal would work?

A diagram I attached (you can view the website) shows a uniform magnetic field of magnetic flux density B[Wb/m^2] parallel to the x-axis. On the xy-plane, an electron of electric charge -e[C] and mass m[kg] departed from the x-axis in the direction of \theta[rad] with a speed of v[m/s]. Then the...

I'm having difficulty with this whole concept I understand that the Lorentz force is the force acting on a charged particle in a magnetic field, and that it is the resultant of the forces due to the electic field and the magnetic field. The situation which I am applying this to is a...

I thought in classical physics, only four forces account for all mechanics: 1 gravitational attraction 2 electromagnetic force 3 nuclear strong force 4 nuclear weak force There is also a Lorentz force on a charged particle moving through a magnetic field. How does classical EM...

Okay here is my work: http://show.imagehosting.us/show/891312/0/nouser_891/T0_-1_891312.jpg and here is my calculations part: http://img136.imageshack.us/img136/5539/lastscan7qc.jpg Problem says: 14. [HRW7 28.P.008.] An electron has an initial velocity of (14.0 j + 21.0 k) km/s and a...

Hi All, Just a thought. The Lorentz force equation as we all know is: F = qE + qvxB. We know that Electrical Field can be written as del(Phi), where Phi is the electrical potential. Also, Force can be written as del(Energy) - correct me on this one. Hence is there a representative term...

Consider a magnetic field with a charge at rest in inertial frame S. From this reference point the particle is not moving wrt the magnetic field and will not experience a Lorentz force. Now consider a frame S' moving wrt S at a constant speed. An observer in this frame would see the charge...