Lorentz force Definition and 202 Threads

Homework Statement Show that the Lorentz Force Law, \frac{dp^{\nu}}{d \tau} = -q U_{\mu} F^{\mu \nu}, is consistent with P^\mu P_\mu= -m^2. Here U is the 4-velocity, F is the Electromagnetic Tensor, and p is the 4-momentum. (Minkowski Space) Homework Equations As stated above. The Attempt at...

I have some confusion about the Lorentz force. First of all, I found that there are two equations for the Lorentz force: one of them is F = qE + qv × B , and the other one is just F = qv × B . What's the difference between them and how do you know which one to use? My other question is: Is the...

Generally we use the left hand rule - (if index finger shows velocity, middle finger shows magnetic field, the thumb points towards force). Recently I also came across a left hand rule for lorentz force- Using your right-hand: point your index finger in the direction of the charge's velocity, v...

https://wikimedia.org/api/rest_v1/media/math/render/svg/a7fd3adddbdfb95797d11ef6167ecda4efe3e0b9 https://en.wikipedia.org/wiki/Lorentz_force#Lorentz_force_in_terms_of_potentials How to write this formula in terms of sums and vector components? What is ##v\cdot\nabla## ? I think it is some...

Hi guys, I am having quite the struggle finding a good resource to explain the difference between the magnetic force associated with moving charged particles (Lorentz Force) and just the regular force exerted by a magnetic field on a magnet or ferromagnetic material. I am trying to apply this...

So I am constructing an analogy between the self replicating fracturing effect on thin films and the path of a charged particle. (Qualitatively, several cracks have similar shapes to charged particle motion) I won't go into the details of the fracture mechanics, so I will only use E+M...

Ok so when we have a current carrying conductor inside a magnetic field there would be Laplace force ##L\times Bi## which is the macroscopic form of the microscopic Lorentz force ##v\times Bq## in a large number of electrons ( or it is not ?) But also there will be hall voltage which will...

Homework Statement An electron with velocity ##\vec{v}_0=8.7*10^4(m/s)## (in the î direction) passing through an area with a uniform magnetic field ##\vec{B}=0.80 T## (in the negative k̂ direction). There's also a uniform electric field in this area. What is the magnitude and direction of...

Hi! I'm getting ready for an exam and want to make sure if I solved some problems correctly. I would be grateful for your feedback :smile: 1. Homework Statement After going through potential difference of 5000 V an electron falls in uniform magnetic field. It’s induction is 0.1T and the...

Homework Statement A relativistic proton is traveling next to a stream of negatively charged particles that are traveling at the same velocity as the proton. I'm to find the force on the proton by transforming the field from the negative stream to a stationary lab frame. Homework Equations f=...

Homework Statement A vertical column of mercury, of cross-sectional area A, is contained in an insulating cylinder and carries a current I0, with uniform current density. By considering the column to be a series of concentric current carrying cylin- ders, derive an expression for the...

I am still a bit puzzled by this video: Does this mean that force exerted on an electrically charged particle facilitated by moving through magnetic field B is due to special relativity, and not virtual photons acting as magnetic force carriers? Thanks

When ions collide with oppositely charged electrodes, do they experience a Lorentz force as they gain or lose electrons? Is there a force, ignoring the repulsion of the positive electrode, in the direction of the blue arrow depicted here? Only information I find is on ionic fluids.

Why does Lorentz force have that particular direction? Why is it perpendicular to the magnetic intesity and the current? Is it cause of some photons' reactions? Thanks

Electric and magnetic parts of Maxwell's equations are kind of similar, so physical effects relating these properties have many 'dual' analogues - with exchanged places. For example in Aharonov-Bohm effect, the phase of charged particle depends on side of magnetic flux tube it comes through...

Here is a problem: Imagine two equally charged capacitor plates parallel to the x-y axis, whose area is large enough compared to the distance between them that fringe effects can be ignored. The bottom plate (at z=0) is + charged, and the top is - charged. The vector field E is therefore...

Why is the Lorentz force calculated in Ansys so low? According to the formula F=B*I*l, it is supposed to be at least 1000 times higher. The model is really simple: a magnetically conductive plate in a static magnetic field inducts the magnetic field from the surrounding space, which makes its...

Let's say we have: \vec{E}=E_x\vec{i}_x+E_y\vec{i}_y+E_z\vec{i}_z and \vec{B}=B_x\vec{i}_x+B_y\vec{i}_y+B_z\vec{i}_z and the Lorentz Force 0=q(\vec{E}+\vec{v}X\vec{B}) which due to \vec{E}X\vec{B}=\vec{B}X(\vec{v}X\vec{B})=vB^2-B(\vec{v}\cdot \vec{B}) and transverse components only...

Hi, I have been studying lorentz force . The book says force experienced by a charge in magnetic field is But velocity is a relative concept . In one frame of reference(inertial frame) I might observe the charge moving with some velocity and in the 2nd frame(inertial too) I might observe the...

When current flows through the armature winding of a dc motor, what exactly happens in there that produces the torque? Is there a force due to the interaction between two magnetic fields or Lorentz force acts on the conductor electrons? Basically, why does motoring effect take place? Is it due...

Hello, I am trying to build a motor. Just a prototype I guess and learning at the moment so just simple stuff but I can't make it work.. I have seen the examples of a homopolar motor and understand the direction of force due to Lorentz force. To be simple I don't want, and don't see the need...

Hi, I am new here, but there is a question that really bugs me :-(. In Lorentz force why was the velocity defined as relative to the observer and not relative to thesystem generating the magnetic field. By defining it relativ eto the system relativity is not needed to explain how an observer...

I'm building a system that is using the Lorentz force principle, of when a wire is placed in a magnetic field(##B##) with length(##L##) and has current flowing(##I##) there is a force = ##IL \times B## that would move the wire. I want to take into account of every single thing that will happen...

Hello, I have been wondering this for a while and have only recently thought to ask here. The Lorentz force is the interaction of a moving charge in a magnetic field, it doesn't seem to have any sort of physical force applied to it, only the magnetic interaction. I was wondering, if there is...

Homework Statement http://www.solutioninn.com/physics/electricity-and-magnetism/magnetic-fields/particle-with-charge-2.15uc-and-mass-3.20-x-10-11-kg-is I am just going to link this because I don't know how to draw a nice diagram like that and put it here. But essentially that is the question...

Homework Statement Show that two measurements F1 and F2 of magnetic force at a fixed point are sufficient enough to determine B at that point as (see picture) provided v1 and v2 are orthogonal. 2. Homework Equations F = qv x B Bz = cFx/(qvy) By = cFz/(qvx) Bx = cFy/(qvz) The Attempt at a...

From the diagram above, there are two types of wires a straight wire and a non-straight wire(zig-zag shaped wire), that are both placed inside a magnetic field(B), and have current flowing in both of them as well. The straight wire will experience a force and will move towards the left as...

The situation is probably well known by many of you. The setup is at rest realtive to the B-field while the rod is moving at a constant velocity. I have been thinking about the connection between the Lorentz force and Maxwell 3 and looking stuff up about it. The first question is wheither only...

When a wire( that has the flow of I) is placed inside a magnetic field(B) experiences the Lorentz force and beings to accelerate in the uniform and constant magnetic field, there is no induced EMF correct? Only when it starts to exist the magnetic field there is change in flux. And there is...

Homework Statement A charged particle (m=1.673*10^-27 kg) exists in a region with E=10 kV/m in the x direction and B=1T in the y direction. If the particle moves without being deflected calculate its kinetic energy. Homework Equations F=Q(E+u x B) and KE=1/2 mu^2 where u is velocity. This is...

Hello Physics forum, I have come here seeking for some experienced help about a doubt that to some extent is not letting me advance on my studies of electromagnetism. Basically is about the magnetic (B) field, and more specifically, about the force at each point of the vector field (The lorentz...

Where is the glitch? 1. Let a single free electron move along x-axis with constant speed Vx. It encounters magnetic field on its right side, so the Lorentz force accelerates it along y-axis and it gains speed Vy. --- Glitch or pass? 2. The electron does not slow down in x direction when...

Two part inquiry PART I Situation: I have a B-field and I'm pulling a straight piece of wire through that B-field You pull the wire perpendicularly through the B-field at velocity v; charges between points a and b will experience the Lorentz Force and will begin to move along...

Hi, I am trying to derive the Lorentz force law in the following form: q \frac{dw^\mu}{d\tau} = q w^\mu \partial_\nu A_\sigma \epsilon_\mu^{\nu \sigma} by varying the following Lagrangian for a classical particle: S = \int d^3 x \left( -m \int d\tau \delta(x-w(\tau) ) + q \int d\tau...

When a wire is placed in a magnetic field and current flows in that wire work is done on the wire and be calculated: 1) W = Fd 2) F = IL x B 3) W = ( IL x B )x d Must there be any derivations beyond what is above? If everything is "given" or... measured via instruments. Then...

When the Lorentz force is applied on a wire that has current flowing in a magnetic field, by changing the direction of the electron(not it's KE) would this possibly change the direction of the Lorentz force? Can the wire be controlled in a way that the force's direction stays the same path?

When a wire has current I in a magnetic field B, there is the Lorentz force is it considered a conservative force or not? Please do explain as to why it is.

When a wire is placed in a magnetic field, Lorentz force acts on an electron in a direction perpendicular to velocity and to the magnetic field, since the magnetic force is perpendicular to the velocity the electron will only change direction with no velocity change, what happens after that, I...

I recently read Griffiths paper on Hidden momentum, and still didn't found it complete. Following is the short summary. The usual setup of current carrying loop and a charge lying nearby, according to the paper, Shockley and James presented the problem, that is, when we let the current die...

What is the formula to evaluate Lorentz force on a curved current carrying wire in a non-constant magnetic field (given by some known vector field). The standard form of Lorentz force (Fb=BxlI) when B and the wire's length 'l' are constants does not account for this case, nor does the...

Greetings All - Per F=BIL I can calculate quantity of Force on coil (or magnet), when I draw certain amount of current from the generator. So I need help in calculating the Force and then weight equivalent of it. Let's say I have Single coil [with 300 turns] generator [wire length = 92...

Greetings, I am trying to to show that the force in this form: \dot{P}=e(\vec{∇}\vec{A})\vec{\dot{x}}-e\vec{∇}\phi Is equal to the lorentz force. I have been trying the approach of some sort of vector identity but have not gotten anywhere. The equation and where I am trying to get...

BCS theory is able to derive the London equations and the Meißner-Ochsenfeld effect. Experimentally the Meißner-Ochsenfeld effect can be demonstrated via levitating superconducting rings. So we have the usual Lorentz force acting on the Cooper pairs carrying the current. However in order to...

How do we say that F=BIL SINΘ using the SI units?:confused: Newton(N)= Weber/m2 * ampere*meter. please explain as soon as possible.:approve:

Homework Statement > Figure 1: > > A spool is hung on a spring. A part of the coil hangs in front of a > homogeneous magnetic field. The coil is incorporated in an electrical > circuit. See Figure 1. > > the coil KLMN has a rectangle shape, has a height of 10.0 cm, a width > of 8.0 cm, and...

Hi, I'm having a major issue trying to work out where the resultant lorentz force might act when I have a wire coiled around a doughnut (toroid) shape. Am I right in saying that there will be a resultant lorentz force acting to crush the doughnut because there will be a slightly denser...

Hi all! First, this is neither a part of homework, university or anything like that , it is my own wondering. I have been searching a lot for how to calculate the Lorentz force acting on a single current carrying wire in Earth´s magnetic field which is 0.6 Gauss. for say a wire of voltage...

Why doesn't a stationary charge experience a magnetic force? And why does a moving charge produce a magnetic field? From a previous thread on the topic I understand it is from the relativistic interpretation of its electrostatic field. So then why shouldn't it affect a stationary charge?

Homework Statement From Zangwill, Chapter 2. Suppose that the instantaneous forces on a charge, q, when it is moving with velocities \vec{v}_1 or \vec{v}_2, are \vec{F}_1 and \vec{F}_2, respectively. Without choosing a coordinate system, show that \vec{B}(\vec{r}) can be determined by working...

If a particle of mass m and charge q (where q can be negative or positive, and the velocity should be positive if q is positive and negative if q is negative) is passed through an electric field of potential Vd, what is the velocity v of the particle? Or possibly this should be a vector...