What is magnetic potential energy?

In summary: So, in summary, the magnetic field does not do work directly, but it can transfer energy to the electric field which can then do work on charged particles. This is a topic that can be further elaborated on, but it is important to understand the interdependence of the electric and magnetic fields in order to fully grasp the concept of work in this context.
  • #1
sudu.ghonge
36
1
We know that a Magnetic field does no work. Then how does an inductor store energy (1/2 LI2)? When that stored energy is needed, it can be retrieved back and clearly it can be used to do some work. In a fix here.
 
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  • #2
Who says a mag field does no work? Who? Mag fields store energy then transfer said energy to the form of electric, electromagnetic, thermal, kinetic, and/or chemical energy domain(s). Have you studied physics or EE extensively? Just curious why you make such sweeping generalizations such as a mag field doing no work, as if it were undisputed gospel? Nothing personal but what is the basis for saying mag fields do no work?

The only reason some give are the Lorentz force relations where mag force acts normal to a charge carrier's velocity. In this case the mag Lorentz force, Fm = quXB, is indeed not doing work on the charge carrier. But E & B fields are mutual & interdependent so that one of them, or both, can do work on dipoles, motors, etc. Also, if an inductor de-energizes into a passive network loop, the time varying B field includes an E field which does work on the charges. B transferred its energy to E which can do work on charges.

This is a topic which cannot be explained in a few posts. I will elaborate if needed.

Claude
 
  • #3
Well, the Magnetic field still does no work. It is the induced electric field that does the work. Got this cleared from somewhere and partially from the second half of your answer.

This is a topic which CAN be explained in a single post. I will elaborate if needed.
 
  • #4
It's better to think of the magnetic field and electric field as part of the same thing: the electromagnetic field. Even if you want to make a distinction, the magnetic field still does work on charged particles through their magnetic dipole moments.
 
  • #5


Magnetic potential energy is the potential energy stored in a magnetic field. This energy is a result of the interaction between a magnetic field and a magnetic material, such as an inductor. While it is true that a magnetic field does not do work in the traditional sense, it does have the ability to store energy.

In an inductor, the magnetic field is created by the flow of electric current through a coil of wire. As the current flows, it creates a magnetic field around the coil. This magnetic field has the potential to do work, as it can induce a current in nearby conductors or attract or repel other magnetic materials.

The amount of energy stored in an inductor is determined by the inductance of the coil (L) and the current flowing through it (I). As the current increases, so does the magnetic field and thus the potential energy stored in the inductor. This relationship is described by the equation 1/2 LI^2, where L is the inductance in henries and I is the current in amperes.

When the stored energy is needed, the inductor can release it back into the circuit. This is commonly seen in devices such as transformers, where the energy stored in the inductor is used to transfer power from one circuit to another. In this way, the magnetic potential energy is converted into other forms of energy, such as electrical energy or mechanical energy.

In conclusion, while a magnetic field may not do work in the traditional sense, it does have the ability to store energy in the form of magnetic potential energy. This stored energy can then be retrieved and used to do work when needed. This concept is crucial in understanding the behavior of inductors and other magnetic materials in various applications.
 

What is magnetic potential energy?

Magnetic potential energy is the energy that is stored in a magnetic field. It is the potential for a magnetic field to do work on a magnetic object.

How is magnetic potential energy different from other forms of potential energy?

Magnetic potential energy is unique in that it is dependent on the orientation of the magnetic field and the magnetic properties of the object. It is also a conservative force, meaning that it can be converted into other forms of energy without loss.

What are some real-life examples of magnetic potential energy?

Some examples of magnetic potential energy include a compass needle aligning with the Earth's magnetic field, a door being held closed by a magnet, and a speaker converting electrical energy into sound waves through the use of a magnetic coil.

How is magnetic potential energy calculated?

The formula for calculating magnetic potential energy is U = -m*B, where U is the potential energy, m is the magnetic dipole moment, and B is the strength of the magnetic field. The negative sign indicates that the potential energy is a maximum when the magnetic moment is aligned with the field.

Why is understanding magnetic potential energy important?

Understanding magnetic potential energy is important in various fields of science, including physics and engineering. It helps in the design and operation of devices that utilize magnetic fields, such as electric motors, generators, and MRI machines. It also plays a role in understanding the behavior of particles in the Earth's magnetic field and in studying the properties of materials with magnetic properties.

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