Electric Motors
... Magnets have been used for centuries to help people navigate the globe. You have seen them holding papers on a refrigerator or spinning the needle in a compass. Magnets produce magnetic fields that attract certain metals (iron, nickel, cobalt). This magnetic effect comes from a special alignment of ...
... Magnets have been used for centuries to help people navigate the globe. You have seen them holding papers on a refrigerator or spinning the needle in a compass. Magnets produce magnetic fields that attract certain metals (iron, nickel, cobalt). This magnetic effect comes from a special alignment of ...
Snímek 1 - Cesta k vědě - Gymnázium Jaroslava Seiferta
... and the external magnetic field means the two states no longer have the same energy. The energy of a magnetic moment μ when in a magnetic field B0 (the zero subscript is used to distinguish this magnetic field from any other applied field) is given by the negative scalar product of the vectors: ...
... and the external magnetic field means the two states no longer have the same energy. The energy of a magnetic moment μ when in a magnetic field B0 (the zero subscript is used to distinguish this magnetic field from any other applied field) is given by the negative scalar product of the vectors: ...
Chapter 27 Questions
... Measurements indicate that the maximum torque exerted on the loop by the field is 8 X 10-3 N·m. a) Calculate the current in the coil. b) Would the value found for the required current be different if the 225 turns of wire were used to form a single-turn coil with the same shape of larger area? Expla ...
... Measurements indicate that the maximum torque exerted on the loop by the field is 8 X 10-3 N·m. a) Calculate the current in the coil. b) Would the value found for the required current be different if the 225 turns of wire were used to form a single-turn coil with the same shape of larger area? Expla ...
EECS 215: Introduction to Circuits
... Because a circular loop exhibits a magnetic field pattern similar to the electric field of an electric dipole, it is called a magnetic dipole ...
... Because a circular loop exhibits a magnetic field pattern similar to the electric field of an electric dipole, it is called a magnetic dipole ...
Magnetic Fields
... It is important to note that magnetic fields are force fields and therefore we need to represent the lines as arrows. In fact we define the direction of a magnetic field as the direction a compass would point in that field. In a permanent magnet these lines go from north to south. ...
... It is important to note that magnetic fields are force fields and therefore we need to represent the lines as arrows. In fact we define the direction of a magnetic field as the direction a compass would point in that field. In a permanent magnet these lines go from north to south. ...
MAGENTIC FIELD
... connect the ammeter through the unfused 20A socket!! 3. Orient the plane of the wires so they align with the compass needle. Rotate the compass case to zero the measuring needles (the long needles). Be patient and give the needle time to settle, and then make fine adjustments. It is critical that th ...
... connect the ammeter through the unfused 20A socket!! 3. Orient the plane of the wires so they align with the compass needle. Rotate the compass case to zero the measuring needles (the long needles). Be patient and give the needle time to settle, and then make fine adjustments. It is critical that th ...
Make Your Own Compass
... wood and placed in bowl of water where it would float on the surface. The needle would spin in the water until it pointed north. This discovery, along with addition of a ring around the needle that was used to identify specific directions, led to the invention of the mariner’s compass in 1200 A.D. Y ...
... wood and placed in bowl of water where it would float on the surface. The needle would spin in the water until it pointed north. This discovery, along with addition of a ring around the needle that was used to identify specific directions, led to the invention of the mariner’s compass in 1200 A.D. Y ...
Magnetism
... but tend to lose their magnetism easily. Hard magnetic materials (for example nickel) tend to retain their magnetism. ...
... but tend to lose their magnetism easily. Hard magnetic materials (for example nickel) tend to retain their magnetism. ...
Magnetism
... Mx and μWb (100 Mx) are cgs units. MKS system: meter-kilogram-second. This system defines larger units of a more practical size. Wb (1 × 108 Mx) is an MKS unit. SI: Systeme Internationale. Basically another name for the metric system. SI units provide a worldwide standard in mks dimensions; ...
... Mx and μWb (100 Mx) are cgs units. MKS system: meter-kilogram-second. This system defines larger units of a more practical size. Wb (1 × 108 Mx) is an MKS unit. SI: Systeme Internationale. Basically another name for the metric system. SI units provide a worldwide standard in mks dimensions; ...
Electric Motors
... Magnets are named for a region in Asia Minor known as Magnesia where people noticed that some rocks were attracted to one another. One of the earlier uses of magnets was in China in the early 11th century in compasses – the needle was made from magnesia, which acted as a magnet that automatically or ...
... Magnets are named for a region in Asia Minor known as Magnesia where people noticed that some rocks were attracted to one another. One of the earlier uses of magnets was in China in the early 11th century in compasses – the needle was made from magnesia, which acted as a magnet that automatically or ...
Magnet
A magnet (from Greek μαγνήτις λίθος magnḗtis líthos, ""Magnesian stone"") is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, and attracts or repels other magnets.A permanent magnet is an object made from a material that is magnetized and creates its own persistent magnetic field. An everyday example is a refrigerator magnet used to hold notes on a refrigerator door. Materials that can be magnetized, which are also the ones that are strongly attracted to a magnet, are called ferromagnetic (or ferrimagnetic). These include iron, nickel, cobalt, some alloys of rare earth metals, and some naturally occurring minerals such as lodestone. Although ferromagnetic (and ferrimagnetic) materials are the only ones attracted to a magnet strongly enough to be commonly considered magnetic, all other substances respond weakly to a magnetic field, by one of several other types of magnetism.Ferromagnetic materials can be divided into magnetically ""soft"" materials like annealed iron, which can be magnetized but do not tend to stay magnetized, and magnetically ""hard"" materials, which do. Permanent magnets are made from ""hard"" ferromagnetic materials such as alnico and ferrite that are subjected to special processing in a powerful magnetic field during manufacture, to align their internal microcrystalline structure, making them very hard to demagnetize. To demagnetize a saturated magnet, a certain magnetic field must be applied, and this threshold depends on coercivity of the respective material. ""Hard"" materials have high coercivity, whereas ""soft"" materials have low coercivity.An electromagnet is made from a coil of wire that acts as a magnet when an electric current passes through it but stops being a magnet when the current stops. Often, the coil is wrapped around a core of ""soft"" ferromagnetic material such as steel, which greatly enhances the magnetic field produced by the coil.The overall strength of a magnet is measured by its magnetic moment or, alternatively, the total magnetic flux it produces. The local strength of magnetism in a material is measured by its magnetization.