Linked Questions
33 questions linked to/from How can magnets be used to pick up pieces of metal when the force from a magnetic field does no work?
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Work done by magnetic field [duplicate]
I know Lorentz force don't do any work. but I want to know whether any type of magnetic field do a work or not.
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How can magnetic fields have energy and yet be unable to do work with that energy? [duplicate]
Magnetic fields can't do work. However, we use the following equation to describe the energy density of a magnetic field.
$u = \frac{B^2}{2\mu_0}$
The term energy density suggests that the magnetic ...
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Questions about Magnetic field [duplicate]
I have two questions about Magnetic Field.
Given a particle with mass m, charge q and uniform B field.
B is going into the page, and particle is moving to the right
Like this. The textbook says ...
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Work done by magnetic forces [duplicate]
I have read in textbooks (such as Griffiths electrodynamics) that magnetic forces do no work. Then i don't see how a magnetic force does no work when a magnet is attracting or repelling another magnet....
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Magnetic Forces and Junkyard Magnets: What's Going On? [duplicate]
In my electromagnetic theory class, I learned that magnetic forces do no work. This is easy to see when observing a cyclotron; the speed never changes, so the kinetic energy never changes and ...
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Zero work by magnetic field but still motion of particle? [duplicate]
I know from ${\bf F}=q({\bf v}\times {\bf B})$ the force is perpendicular to displacement and so work by magnetic field is always zero. But then how is that a magnet is able to displace any magnetic ...
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Work by magnetic field [duplicate]
we all know that magnetic field doesn't work....if a current carrying element pulls a metal piece then work is done by the source or the battery not the field.....now let us assume that a bar magnet ...
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Work done by a magnetostatic field [duplicate]
How does a (static) magnetic field accelerate objects (like an iron nail) if we are taught that the magnetic force does always zero work?
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How does permanent magnets attract each other if the $B$-field can do no work? [duplicate]
How can two permanent magnets do work on each other?
If you put two magnets with opposite poles facing each other they will attract each other. If you put them with the same poles facing each other ...
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Contradiction in the fact that magnetic fields do zero work [duplicate]
Consider a metallic rod hung by two springs (symmetrically), a magnetic field exists out of the plane of our system. At t = 0, we switch on a battery which produces current in wire (left to right in ...
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Conceptual question about Magnetism? [duplicate]
I am confused about Magnetic force whether it does work or NOT because i think that the battery does the word and the magnetic force only redirects the work done by battery into some displacement etc. ...
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If is work done by magnetic field is 0 then why does 2 magnets attract when kept together? [duplicate]
If 2 magnets are kept close to each other they attract then shouldn't it be considered as work done by magnetic field?
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Magnetic field and magnet [duplicate]
We know that magnetic does not do any physical work . Now consider; we attached a magnet in a wall with help of a tape. Now we bring a magnet near to other magnet and released we see that magnet will ...
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Repulsion between two magnets [duplicate]
When we bring a bar magnet towards another bar magnet such that their similar poles are facing each other, the other bar magnet moves due to repulsion. How this is possible if magnetic force can't do ...
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Magnetic force and work done [duplicate]
If magnetic force do no work at all then how do magnets attract or repel each other?
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