All Questions
Tagged with electromagnetism forces
525
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What happens when both magnetic field and electric field is applied to a charged particle?
Now what exactly happens when magnetic field and electric field is applied perpendicularly? What happens when they are not perpendicular?
In the question, it says that a magnetic field and electric ...
14
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7
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Why does a charge need to have a velocity to experience force in a magnetic field?
While studying magnetism, I learned that force on a charged particle inside a magnetic field is
$$\mathbf{F}=q(\mathbf{v}\times\mathbf{B})$$
where all symbols have their usual meaning, which implies ...
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What is the physical meaning of the torque term involving the magnetic displacement force?
In Zangwill's Modern Electrodynamics the magnetic torque is derived in Eq. 12.63 to be
\begin{equation}
\mathbf{N}(\mathbf{r}_0) = \mathbf{m} \times \mathbf{B}(\mathbf{r}_0) + \mathbf{r}_0 \times \...
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Force on an iron ball in a homogeneous magnetic field [duplicate]
Just a simple question. If I have a homogeneous magnetic field and I put an iron ball into this field, it would be attracted to the source of the magnetic field. But how do I calculate the force that ...
2
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3
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What is magnetic shear?
Can someone please summarise to me what exactly magnetic shear is? I know shear as $\tau=F/A$, and intuitively interpret is as, eg, a force on an object and the friction response being shear forces. ...
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Force between two current carrying conductors
lets say I have two wires. each has a magnetic field due to its current. this magnetic field is present in the other wire causing a force in that other wire. Now I understand that changing the current ...
2
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1
answer
113
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Why can we calculate force on a dipole from torque?
In the Feynman lectures he derives the (mechanical) energy of a dipole
$$ U = -\boldsymbol{\mu}\cdot \boldsymbol{B} + \mathrm{constant}$$
by considering only the torque on it in a uniform field. He ...
1
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127
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Coilgun projectile force calculation
Please excuse me if I am completely wrong because I am a 9th grader but I hopefully am able to explain briefly about my problem. I was trying to create a function to calculate the Force of an iron ...
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2
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Couple acting on quadrupole due to a point charge
I wish to find the couple acting on the quadrupole due to q', assuming r>>a. Here is my working:
Force acting on -2q:
$E_{at \ -2q} = \frac{q'}{4\pi\epsilon r^2} \\
F_1 = (-2q) E = \frac{-2qq'}{...
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Could you calculate the force between two NON-PARALLEL, straight current carrying wires?
Just like there are ways to solve for the force between two straight parallel wires, what is the way we could find the force between non-parallel wires?
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Repulsive force between electrons at relativistic speeds
What happens to the repulsive force between two electrons, once one of the electrons travel at relativistic speeds?
Let's consider two electrons in an atom with magnetic dipole moment, one of which is ...
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Is there a ponderomotive force due to a traveling wave?
Imagine a traveling, EM wave passing through some plasma. The waveform is given by the vector potential:
$A = (0, -\frac{cE_0}{\omega_0}\cos\eta, 0)$
where $\eta = \omega_0t-k_0x$ is the phase. From ...
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Which equation is most valid for finding power dissipation in a induced magnetic pendulum system?
Considering a set up where a conducting pendulum oscillates between two permanent magnets, I want to somehow calculate the power dissipated by the magnetic braking force the magnets provide, in order ...
2
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What are the conditions according to which the levitation force between a magnet and a superconducting material tends to zero?
According to this article, for a disk-like superconductor and a magnet, if the radius of the superconductor tends to zero or the radius of the magnet tends to infinity, it seems that the levitation ...
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How great is the net force exerted on a superconducting material of a small size being subjected to an external uniform magnetic field?
Assume that we have a very tiny spherical or disk-like superconducting material that is subjected to an externally uniform magnetic field. I want to know if the net force that accelerates the ...