All Questions
Tagged with electromagnetism forces
524
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How positively charged protons remain glued to each other while they should repel each other out of nucleus? [duplicate]
Possible Duplicate:
Protons' repulsion within a nucleus
How positively charged protons remain glued to each other while they should repel each other out of nucleus?
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Is there an intuitive explanation for why Lorentz force is perpendicular to a particle's velocity and the magnetic field?
The Lorentz force on a charged particle is perpendicular to the particle's velocity and the magnetic field it's moving through. This is obvious from the equation:
$$ \mathbf{F} = q\mathbf{v} \times \...
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2
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We know that the protons in a nucleus are positively charged. So why does the nucleus stay intact? [duplicate]
We know that the protons in a nucleus are positively charged, whereas the neutrons do not possess a charge; we also know that unlike charges attract. So why does the nucleus stay intact, even though ...
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Interaction speed between electric charges and magnetic materials
Einstein said that the speed of a matter in universe cannot exceed the speed of light.
Is it correct for electric force transmission speed from one electric charge to other one?
What is transmission ...
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2
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Does constraint for speed of Electric and magnetic fields violates Conservation of momentum or Newton's third law?
I'm just a beginner so bear with me. Consider two frames at rest wrt to each other separated by distance enough for light to take a minute or so. At a given instant we create two large dipoles by some ...
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Is the EmDrive, or "Relativity Drive" possible?
In 2006, New Scientist magazine published an article titled Relativity drive: The end of wings and wheels1 [1] about the EmDrive [Wikipedia] which stirred up a fair degree of controversy and some ...
user8616
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Magnetic force and work
If the magnetic force does no work on a particle with electric charge, then:
How can you influence the motion of the particle? Is there perhaps another example of the work force but do not have a ...
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What is degeneracy pressure?
What is "degeneracy pressure"?
I know there are 4 fundamental forces- EM, gravity, weak and strong. But then degeneracy comes along ubiquitously in everything right from neutron star to the ...
- 2,853
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Lorentz force law in Newtonian relativity
I know that in special relativity Electric and Magnetic fields mix together in different reference frames, but my question is about classical mechanics.
It seems weird to me is that the Lorentz Force ...
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44
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5
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Can the Lorentz force expression be derived from Maxwell's equations?
The electromagnetic force on a charge $ e $ is
$$ \vec F = e(\vec E + \vec v\times \vec B),$$
the Lorentz force. But, is this a separate assumption added to the full Maxwell's equations? (the ...
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What is the force between two magnetic dipoles?
What is the force between two magnetic dipoles?
If I have two current loops parallel to each other with currents $I_1$ and $I_2$ and radii $R_1$ and $R_2$ a distance $z$ from each other, what is the ...
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Work done by the Magnetic Force
The magnetic part of the Lorentz force acts perpendicular to the charge's velocity, and consequently does zero work on it. Can we extrapolate this statement to say that such a nature of the force ...
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3
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How does one calculate the force applied on an object by a magnetic field?
I've tried very hard to find an answer to this question, and every path leads me to an abstract discussion of fundamental forces. Therefore, I will propose two very specific scenarios and see if they ...
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2
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What is the cause of the normal force? [duplicate]
I've been wondering, what causes the normal force to exist?
In class the teacher never actually explains it, he just says "It has to be there because something has to counter gravity." While I ...
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What was meant by the 'ponderomotive force' as understood by Minkowski?
Skimming through Minkowski's famous 1907 paper, he uses the term ponderomotive force.
What does he mean by this?
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3
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Why exactly does current carrying two current wires attract/repel?
When to parallel wires carrying currents in same direction $I_1$ & $I_2$.
The MIT Physics Demo Forces on a Current-Carrying Wire this video demonstrates that effect.
My question is, why exactly ...
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Pollen Particle Attracted to TV due to Which Force?
A pollen particle has no charge so I cannot understand how the Lorentz force $\bar{F} = q \bar{E} + q(\bar{v} \times \bar{B} )$ could explain the event. I speculated that it is because of the electric ...
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3 current loops with non-conservation of momentum, when one specifically considers SIGNs
Thought experiment I.
Consider two loops of wire, 2 small dipoles B and C , with a common axis z (facing each other) and (say) 30 cm apart B to C. At the speed of light, information (including a ...
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existence of other forces obeying inv square law
Is there any restriction in what we know of physics to the existence of other type of forces that obey the inverse square law in 3 dimensions.
I mean other than electromagnetic and gravitational.
...
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How is a magnetic field translated into physical force?
Related to this question
Where do magnets get the energy to repel?
If I have a magnet repelling another, eg one in my hand, the other being pushed along the desk, how do the each of the magnet's ...
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What's the core difference between the electric and magnetic forces?
I require only a simple answer. One sentence is enough... (It's for high school physics)
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How can I stand on the ground? EM or/and Pauli?
There is this famous example about the order difference between gravitational force and EM force. All the gravitational force of Earth is just countered by the electromagnetic force between the ...
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How can we make an order-of-magnitude estimate of the strength of Earth's magnetic field?
The source of Earth's magnetic field is a dynamo driven by convection current in the molten core. Using some basic physics principles (Maxwell's equations, fluid mechanics equations), properties of ...
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Where do magnets get the energy to repel?
If I separate two magnets whose opposite poles are facing, I am adding energy. If I let go of the magnets, then presumably the energy that I added is used to move the magnets together again.
However, ...
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