Electromagnets
... A reed switch has two thin pieces of iron inside it. If a magnet is held near the switch, the pieces of iron are magnetised and touch each other. A reed switch can also be switched on using an electromagnet. Any switch that is worked by electricity is called a relay. Relays are used to make things s ...
... A reed switch has two thin pieces of iron inside it. If a magnet is held near the switch, the pieces of iron are magnetised and touch each other. A reed switch can also be switched on using an electromagnet. Any switch that is worked by electricity is called a relay. Relays are used to make things s ...
Electromagnetic Forces
... To further his investigation, he set up several compasses around a wire with no current and noticed that all the needles pointed North. Then, after he produced a current in the wire, the compass needles pointed in different directions to form a circle. He then concluded that the current had produced ...
... To further his investigation, he set up several compasses around a wire with no current and noticed that all the needles pointed North. Then, after he produced a current in the wire, the compass needles pointed in different directions to form a circle. He then concluded that the current had produced ...
Examination questions Division of Condensed Matter Physics
... 7. Spectroscopic and scattering methods in studies of dynamics of solids: dielectric spectroscopy, reflection and absorption of infrared, visible and ultraviolet radiation, scattering of neutrons and charged particles. 8. Thermodynamic properties of materials: heat capacity, the simplest models of s ...
... 7. Spectroscopic and scattering methods in studies of dynamics of solids: dielectric spectroscopy, reflection and absorption of infrared, visible and ultraviolet radiation, scattering of neutrons and charged particles. 8. Thermodynamic properties of materials: heat capacity, the simplest models of s ...
Magnetic stripes on the ocean floor: a lab simulation
... forming the ocean floor was a key piece of evidence convincing most geologists that the theory of plate tectonics was correct. This teacher demonstration shows how this works. There are two closely related activities which teachers may wish to tackle at the same time. These are: ...
... forming the ocean floor was a key piece of evidence convincing most geologists that the theory of plate tectonics was correct. This teacher demonstration shows how this works. There are two closely related activities which teachers may wish to tackle at the same time. These are: ...
Magnetism - Worth County Schools
... - different locations than the earth’s geographic poles ( N magnetic pole – Canada) - the compass – is a freely rotating magnetic needle that responds to the earth’s magnetic poles by pointing North. - Lodestone (magnetite) – a natural magnet was used as the first compass on ships. ...
... - different locations than the earth’s geographic poles ( N magnetic pole – Canada) - the compass – is a freely rotating magnetic needle that responds to the earth’s magnetic poles by pointing North. - Lodestone (magnetite) – a natural magnet was used as the first compass on ships. ...
Multiferroics
Multiferroics have been formally defined as materials that exhibit more than one primary ferroic order parameter simultaneously (i.e. in a single phase), and many researchers in the field consider materials to be multiferroics only if they exhibit coupling between primary order parameters. However, the definition of multiferroics can be expanded to include non-primary order parameters, such as antiferromagnetism or ferrimagnetism.The four basic primary ferroic order parameters areferromagnetismferroelectricityferroelasticityferrotoroidicityThe last is a topic of some debate, as there was no evidence for switching ferrotoroidicity until recently.Many multiferroics are transition metal oxides with perovskite crystal structure, and include rare-earth manganites and -ferrites (e.g. TbMnO3, HoMn2O5, LuFe2O4 and recently, ""PZTFT"",). Other examples are the bismuth compounds BiFeO3 and BiMnO3, non-perovskite oxide LiCu2O2, and non-oxides such as BaNiF4 and spinel chalcogenides, e.g. ZnCr2Se4. These alloys show rich phase diagrams combining different ferroic orders in separate phases.Apart from single phase multiferroics, composites and heterostructures exhibiting more than one ferroic order parameter are studied extensively. Some examples include magnetic thin films on piezoelectric PMN-PT substrates and Metglass/PVDF/Metglass trilayer structures.Besides scientific interest in their physical properties, multiferroics have potential for applications as actuators, switches, magnetic field sensors or new types of electronic memory devices.