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Magnetism: Real-life applications - Coggle Diagram
Magnetism: Real-life applications
Magnets for Detection: Burglar Alarms, Magnetometers, and MRI
a magnetometer is much more sophisticated piece of machinery for detecting the strength of magnetic fields
compass is kinds of magnetometers respond to planet's magnetic field
buglar alarm consists of a contact swicth which may be mechanical or magnetic, that responds to changes in the environment and sends signal to noisemaking device
magnetometers used by astronomers detect the strength and sometimes the direction of magnetic fields surrounding Earth and other bodies in space
magnetic resonance imagining or MRI permits doctors to make intensive diagnoses without invading the patient's body either with surgical knife or X-rays
Magnets for Projecting Sound: Microphones, Loudspeakers, Car Horns, and Electric Bells
the microphone's diaphragm has negative charged plate of capacitor which will vibrates at the same frequency as it hit by sound waves.
loudspeaker contains a circular permanent magnet which surrounds an electrical coil and is in turn attached to a cone-shaped diaphragm.
the current induces an alternating magnetic field, causes the coil to vibrate. This in turn vibrates the cone-shaped diaphragm, and the latter reproduces sounds generated at the source
car horn also uses magnetism, pressing the steering wheel will depresses an iron bar that passes through an electromagnet surrounded by wires from the car's battery
electromagnetically induced vibration is secret behind another noise-making device, a vibrating electric doorbell used in many apartment
Recording and Reading Data Using Magnets: From Records and Tapes to Disk Drives
the idea of using magnetism to record sound is much older than computers or compact discs (CDs)
magnetic tape is use for master recordings of songs
the master used to create a metal master record disk by means of a cutting head that responded to vibrations from the master tape
the strength of alternating current in turn affect the "recording head", a small electromagnet whose magnetic field extends over section of tape being recorded
loud sounds produce strong magnetic fields and soft ones weak fields
all information becomes embedded on the cassette tape through a process of magnetic alignment
reversal of tape's ,magnetization is easy
the disk drive receives electronic on-off signals from the computer, and translates these into magnetic codes that it records on the surface of a floppy disk.
the disk drive itself includes two electric motors: a disk motor, which rotates the disk at a high speed, and head motor, which moves the computer's read-write head across the disk
stepper motor, ensures that the drive turns at a precise rate of speed, contains its own permanent one cylindrical shape that send signals to rows metal teeth surrounding it
MAGLEV Trains: The Future of Transport?
one promising application of electromagnetic technology relates to a form of transportation is train
magnetic levitation, trains are as far removed from the old stream engines of the Union Pacific as the space shuttle is from the Wright brothers' experimental airplane.
magnetic poles of like direction repel one another which possible to keep one magnet suspended in the air over another magnet
electromagnet can create a magnetic field powerful enough that if used properly, it exerts enough repulsive force to lift extremely heavy object
the advent of superconductivity, the use of extremely low temperatures, which facilitate the transfer of electrical current through a conducting material with virtually no resistance made possible electromagnets of staggering force.
MAGLEV prototypes building began using superconducting coils with strong currents to create a powerful magnetic field
electrical current sent through guideway coils on the track allowed for enormous propulsive force, pushing trains forward at speeds up to and beyond 250 MPH (402km/h
)
the field create a repulsive force capable of lifting a train several inches above a railroad track