Linked Questions

-1
votes
1answer
20k views

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.
5
votes
2answers
2k views

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 ...
0
votes
1answer
2k views

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 ...
2
votes
1answer
524 views

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....
1
vote
1answer
74 views

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 ...
1
vote
0answers
73 views

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 ...
1
vote
0answers
66 views

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 ...
4
votes
0answers
58 views

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?
0
votes
0answers
51 views

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 ...
1
vote
1answer
36 views

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 ...
1
vote
4answers
110 views

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 ...
1
vote
0answers
31 views

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. ...
0
votes
0answers
22 views

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?
0
votes
0answers
16 views

Magnetic force and work done [duplicate]

If magnetic force do no work at all then how do magnets attract or repel each other?
0
votes
0answers
16 views

Can a permanent magnet lift objects without touching it? [duplicate]

I’ve been trying to think through this scenario given the fact that magnetism can not do work. If you hold a permanent magnet close overhead a magnetizable object, and if you slowly lower the magnet ...

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