All Questions
Tagged with electromagnetism forces
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Deriving Lorentz force from relativistic force
By EQ.$72$ of this, Richard Haskell proves Lorentz force law in subsequent sections. During the proof he says that,
Suppose a conductor of charge density $\rho'$ be at rest inside a frame of reference ...
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If friction and normal force are both the components of contact force, shouldn't the friction be repulsive?
Is friction due to intermolecular attractive forces or repulsive ones.
Since both friction and normal force are the components of contact forces, shouldn't friction be repulsive.
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Do the other 3 fundamental forces also warp space-time?
I got this idea from Einstein's insight using the falling elevator. He says, that Gravity really cannot be distinguished from any other force accelerating the elevator.
A bunch of questions on here (...
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Do forces get affected by relativity?
Do forces change their behavior due to the relativity?
For example if a charged particle deflects through an electric field, would the pattern and amount of deflection differ in speeds near speed of ...
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On the infinite range of the electromagnetic force
I am curious as to whether there is a fundamental reason why weak and strong nuclear forces have such a short range whereas gravity and the electromagnetic force seem to have infinite range.
Since ...
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Magnetic force calculation for parallel wires using Maxwell stress tensor. Issue with shear forces
I am trying to calculate the forces in between permanent magnets and ferromagnetic surfaces with the Maxwell stress tensor using image theory and the Biot-Savart law. However I discovered a weird ...
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Why the magnet travels through solenoid faster if we connect a bulb to a solenoid
When a magnet travels linearly through a solenoid at a fast enough velocity if the ends of solenoid are connected to each other, the induced EMF generated and Lenz Law the solenoid opposes the motion ...
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When I push a 24-karat gold bar with my finger, what subatomic physics are at play? [duplicate]
I chose a pure gold bar to eliminate the possibility of any chemical reactions occurring, the same question would apply to any everyday object like a wooden block or a marble. Or it could apply with ...
user350881
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Doubt about Electromagnetic Attraction b/w Electromagnet-Iron vs Electromagnet-Electromagnet
https://www.supermagnete.de/eng/faq/What-is-the-difference-between-the-combination-magnet-magnet-and-magnet-iron
At full contact, the attractive force between a raw magnet and an iron plate is the ...
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Tension generated in a metallic loop placed in a time varying magnetic field [closed]
We have a metallic wire circular loop of resistance $R$, having radius $a$, placed in a magnetic field $\bf{\vec{B}(t)}$. The magnetic field is perpendicular to the plane of the wire.
The magnetic ...
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Why is normal contact force electromagnetic in nature?
I learnt that normal contact force can be interpreted as the restoring force when an object undergoes deformation due to external stress, and it is perpendicular to the surface of contact.
I also ...
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What is the physical significance of the negative sign in the lorentz force equation in presence of magnetic monopole?
This question is similar to that of: Why does the extended Lorentz force law have a negative sign?
The Lorentz force on a magnetic monopole is given as:
$$\vec{F}=q_m(\vec{B}-\vec{v}\times\frac{\vec{E}...
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Cleaning silt off magnets
I gone done a foolish thing; I got my set of spherical (⌀ 5 mm) neodymium magnets covered in of (what is presumably iron based) ferromagnetic silt/sand particles.
With some difficulty, I've been able ...
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Are there any experiments showing any deviation from the conventional formula for the Lorentz force?
I want to know if there are experiments showing that the second term of the Lorentz force formula is measured slightly differently from the conventional $qv×B$ for some fundamental particles.
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How does the Electric field apply a force?
How does a static electric field apply force to charges within its field? I understand that the source of electric fields are charged particles, and the reason charges will attract or repel each other ...
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Is there a more "physically mature" way to think about the right hand rule with electromagnetism?
I've always found using the righthand rule to remember how forces, B-fields, and particle velocities to be intellectually cheating myself a bit. It feels like being able to multiply numbers by using ...
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Are Electric Field lines thought to be "in tension"?
I had a thought the other day about how electric field lines and how they explain like charges repelling and opposites attracting. I read on another post that electric field lines are thought to be &...
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Does a levitating Superconductor experience reistance to motion from the magnetic field if a force is applied?
If one has a superconductor that's being levitated on a track and you apply a force through its c.m. completely parallel to the track it's on (perpendicular to gravity), would there be any kind of ...
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Why this term can be written as the electric force component of the lorentz law?
I am reading Special Relativity and Classical Field Theory by Susskind. In chapter 6, he is deriving the Lorentz force law from the action, and he presents the following equation $$m\frac{d}{dt}\frac{\...
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Is force perpendicular to magnetic field in a bar magnet?
Recently I started this topic. My lecturer used
$$F_{B}=q_{n}B$$
I have two questions in this topic.
By this equation both the magnetic field and Force are in same direction. But aren't they supposed ...
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Modeling particles in electric and magnetic fields (software recommendations)
Does anyone know of free software that would allow me to visually model particles moving in electric and magnetic fields, ideally, including magnetic fields extended/altered by ferromagnetic materials?...
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Question Regarding The Movement of Charges [duplicate]
We know that two electrons repel each other since they have like charges, which means they move in opposite directions. But how can they move if they exert equal and opposite charges, aren't the ...
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Can a net propulsive effect occur between phase shifted antennae?
So this question centers around an electromagnetic thought experiment suggested by the patent titled "Efficient RF electromagnetic propulsion system with communications capability", ...
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Are electric force and strong force equal in magnitude?
Should the electric force and the strong force be equal for a nuclei to be stable? Because if perhaps, the strong force is now more than that of the electric force, then shouldn't the nucleus collapse ...
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Does the force between two magnetic poles ever reach zero?
If we hold two magnetic like-poles together and start to move them away, would the repelling force reach absolute zero at certain point?
In that scenario, as a layman, I think that there is something ...
user342647
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Why does changing the permittivity of the dielectric within a capacitor not have any effect on the electric field opposite the plate?
Utilizing FEMM 4.2, I built a pair of simple parallel plate capacitors, however I oriented them so that the anodes of these capacitors faced each other. As expected, the electric fields of the two ...
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Can we use the concept of a railgun or coilgun to design a small particle accelerator?
A railgun is used as a linear particle accelerator to project projectile at high speeds. Why not use this concept to build a circular rail particle accelerator. A conventional railgun uses extremely ...
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Why can we add the two terms in the Lorentz force?
The term "Lorentz force" in the title refers to (1).
my textbook states:
The Coulomb force is mediated by the electric field and acts on the charge $q$, that is, $\mathbf{F}_e = q\mathbf{E}$...
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A wind tunnel and 2 strong magnets in the wind tunnel creating a very strong field, how would the wind & magnetic force interact?
Sorry if I get some terminologies wrong I am not a physics major :)
If I had a big wind tunnel on earth blowing wind through a strong magnetic field (so the opposite poles of 2 giant magnets creating ...
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My doubt is regarding the lorentz force
Consider a magnetic field in the positive z direction, and a charge +q moves with a velocity along the positive x direction. How do we know in which direction lorentz force on charge will be acting?
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Lorentz force from potential- extra term?
I'm trying to verify the E.M potential energy $U= \int{A_\mu J^\mu} = q(\phi - A_j v^j )$ by using the connection:
$$
F= - \frac{\partial U}{\partial r} + \frac{d}{dt} \frac{\partial U}{\partial v}
$$...
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Force and magnetic field
what is the force on the piece of wire from the infinite conductor?? what is the force on the infinite conductor from the piece of wire??
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Direction of spacetime curvature?
I am honestly new to all. But, I am confused about space time curvature and gravity.
I see in lots of graphs that the spacetime bends when there is a mass in it, and that bend is in the direction of ...
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Do Magnetic forces obey Newton's Third Law? [duplicate]
If we have two magnets and one is brought towards the other, the north of the former magnet is facing north of the latter. Now the other magnet is repelled which is obvious and Newton's third law is ...
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Proving that the magnetic force experienced by a charged particle produces a circular motion
I have a charged particle $q=-1$, $m=1$, moving with a velocity $\mathbf{v} = <\dot{x},\dot{y},0>$, under the influence of a magnetic field $\mathbf{B} = < 0,0,-B>$, where $B > 0$.
I ...
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Why is the cross product used in electrodynamics [closed]
For example, $F = I \times B$. Why would the force be perpendicular to both the magnetic field and the current? Why would the resultant force be totally unlike its 2 sources; this could be likened to ...
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Why don't (electrically charged) particles act on themselves?
As per the Maxwell-Gauss equation, an electron modifies the electrical field around it. Therefore it should act (through an electric force) on itself. Now obviously this force would be directed ...
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How to find velocity as a function of distance/time when force is given as a function of distance?
Let's say force between two particles is given as F=k/r² where 'r' is distance between two particles and k is a constant. I am having trouble in finding velocity as a function of distance between ...
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How does the Lorentz force on a wire create macroscopic movement?
In a a current carrying wire exposed to a magnetic field, the electrons will experience a force and hence, a net displacement from. However it is not clear to me how this causes the wire to bend/move ...
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If contact forces are repulsive then how are we able to pull stuff? [closed]
I searched a lot on internet(especially physics stackexchange) about the nature of contact forces. I came to know through most of them that it is repulsive in nature which surely means that your hand ...
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Formula for Force between two Solenoids
Given two identical solenoids (with appropriate core) $S_0$ and $S_1$ with length=$L$, radius=$R$, number of turns per unit length=$n$. Let these two solenoids be held with the two poles facing each ...
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Does it require greater force to accelerate a charged mass than an equal neutral mass?
Accelerating a charge produces radio-waves which is a form of energy. This energy has to come from somewhere. It would seem to suggest it would require greater force to move a charged mass than an ...
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How is Lorentz Force $BQv=BIl$?
The formula for Lorentz Force on moving charge is $$F=BQv$$ which for current carrying wire is modified to $$F=BQv$$$$=BQ\frac lt$$$$=BIl$$
Where $l$ is the length of the wire inside the magnetic ...
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Electromagnetic force for charges on a surface of discontinuity of the electric field
Suppose we have an infinite cylinder of radius $R$ in vacuum with some surface charge density $\sigma=\sigma(\varphi)$, where $\varphi$ is azimuthal angle. We want to calculate the force acting on one ...
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Generalised Geodesic equation for forces
im wondering if there is a general geodesic equation that describes the forces and how they act. For example I started off with the original nieve derivation of the geodesic equation:
$$\frac{d}{d\tau}...
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Electrostatic potential of a dipole in a non-uniform field
There are numerous derivations for the potential energy of a dipole in a uniform field as:
$$
U = - \boldsymbol{p}\cdot\boldsymbol{E}
$$
But does this hold also for non-uniform fields? Are there any ...
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Force acting on a negative particle in a magnetic field
I have recently learned about magnetic fields and particles. The recent one I have learnt is the right hand rule. The force F acting on a negative particle is always opposite to the force we get from ...
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Would atoms be smaller or larger if the electromagnetic force was slightly weaker?
Some sites claim that atoms would be larger in size if the EM force was weaker, because the electrons would 'orbit', on average, farther from the nucleus....
Other physicists claim that atoms would, ...
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Electric force in general relativity
In general relativity, for two electrons in a space-time how do we define the electric force? Is it such that we have in classical physics or they go away from each other because of the curvature that ...
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If I push someone, what fundamental force do I create?
According to Wikipedia, all forces can be decomposed to four fundamental forces: gravity, electromagnetism, strong interaction and weak interaction.
When I push someone, this generates a force. Which ...
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