Electricity and Magnetism After reading this section you will be able to do the following: Discuss what happens to a compass when a wire with electrical current is near. Describe the relationship between electricity and magnetism. Why does the compass respond when it is near an electrical wire with current flowing through it? We can [...]
Electromagnetic Fields After reading this section you will be able to do the following: Describe the magnetic fields that surround a current carrying conductor. Iron filings scattered in the vacinity of a current carrying wire will reveal a magnetic field perpendicular to the current flow. Magnetic field lines directed out of the page towards the [...]
Exchange Spring Magnet An exchange spring magnet is a magnetic material with high coercivity and high saturation properties derived from the exchange interaction between a hard magnetic material and a soft magnetic material, respectively. Coehoorn et al. were the first able to observe an actual exchange spring magnet.[1] Exchange spring magnets are cheaper than many [...]
The Coming Revolution in MnBi High-Strength Magnets Expensive rare-earth magnets that power high-performance motors could be on the wane within a few years thanks to new materials now emerging from research labs. Motor manufacturers that want to impress engineers often bring up the fact that their high-performance motors use rare-earth magnets. But that may soon [...]
Magnetic Field Characteristics After reading this section you will be able to do the following: Describe magnetic fields in different shaped magnets. Understand the important properties possessed by magnetic lines of force. Magnetic Field In and Around a Bar Magnet As discussed previously, a magnetic field is a change in energy within a volume of [...]
Creation of Magnetic Fields After reading this section you will be able to do the following: Define a magnetic field and explain how it is created. Magnetic Field Creation A magnetic field describes a volume of space where there is a change in energy. As Ampere suggested, a magnetic field is produced whenever an electrical [...]
Magnetic Behavior After this reading this section you will be able to do the following: Perform an experiment to detect what materials are magnetic and explain why you think they are magnetic. Magnetism Just like when the Greeks of the old times discovered the first naturally occurring magnetic stones, or natural magnets, you have been [...]
The Two Ends of a Magnet After completing this section you will be able to do the following: Explain what a compass is and how it is affected by a magnet. Understand how a compass helps us to navigate on the earth. Magnets Most people are familiar with the general properties of magnets but are [...]
Magnetic Domain Dynamics Along the Magnetic Hysteresis Curve Inside Permanent Magnet In the long history of permanent magnet research for more than 100 years, three-dimensional magnetic microscopy has been eagerly awaited to elucidate the origin of the magnetic hysteresis of permanent magnets. In this study, we succeeded in observing the three-dimensional magnetic domain structure of [...]
Why can some materials be turned into magnets? It’s all thanks to magnetic domains In ferromagnetic materials, like iron and nickel, groups of atoms band together in areas called domains. The magnetic strength and orientation, also called the magnetic moments, of the individual atoms in such a domain are aligned with one another and all [...]
Magnetic Domains & Hysteresis Magnetic Domains We know magnets aren’t attracted to everything; if we put a magnet on a wooden wall, it will fall right down. Generally, magnets are attracted to objects that are made of the metals iron, nickel, or cobalt. These materials are called ferromagnetic materials. The reason magnets stick to these [...]
What are Magnetic Domains? According to the properties of substances in an external magnetic field, substances can be divided into five categories: paramagnetic substances, diamagnetic substances, ferromagnetic substances, ferrimagnetic substances and antiferromagnetic substances. A ferromagnetic substance is a substance that is magnetized under the action of an external magnetic field and can maintain its magnetized [...]