Popularizing the Knowledge of Insulating Materials
1. What is a magnetic field?
Answer: around the pole or any of the current loop and the magnetized objects inside and outside, have effect on the magnetic needle or the moving charge, the magnetic force space called magnetic field. It is similar to the electric field, and it also has the characteristics of force and energy.
3. What are soft magnetic materials? What are their features and uses?
Answer: soft magnetic materials refer to ferromagnetic materials with very small remanence and coercive force, such as silicon steel and pure iron. It is characterized by easy magnetization, easy demagnetization and narrow hysteresis loop. Soft magnetic materials are often used to make the core of electrical machines, transformers, electromagnets and other electrical appliances. The characteristic is that it is not easy to magnetize, and it is not easy to lose magnetism, and the hysteresis loop is wide. The magnet magnetic material used to produce all kinds of permanent magnets, speaker and electronic circuit memory components etc.
4, what is the eddy? What are the advantages and disadvantages in production?
Answer: the inner of the conductor in the alternating magnetic field (including the ferromagnetic material) will induce the closed loop current on the cross section perpendicular to the magnetic line of force, called the eddy current.
Advantages: eddy current principle can be used to make induction furnace to smelt metals. Eddy current can be used to make magnetoelectric and inductive electrical instruments. The dampers in the watt hour meter are also made by eddy current principle.
Disadvantages: in the motor, transformer and other equipment, the eddy current will cause additional loss, and the weakening of magnetic field will reduce the efficiency of electrical equipment, and make the capacity of equipment not fully utilized.