Basic Electrical Installation Work

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Strong magnetic fields have high-flux density. 4. 5.14.13 Magnetic fields around permanent magnet. Bar magnet Horse shoe magnet N S N S FIGURE 5.14. These two statements are sometimes called the‘first laws magnetism’and are shown Fig. Lines magnetic flux behave like stretched elastic bands, always trying shorten themselves. Lines magnetic flux pass through space and non-magnetic materials undisturbed. Like poles repel; unlike poles attract. The number lines magnetic flux within magnetic field a measure the flux density. 5. 5. The places magnetic material where the lines flux are con- centrated are called the magnetic poles. . The region space through which the influence magnet can be detected called the magnetic field that magnet. The magnetic fields around a permanent magnet are shown Figs 5. The symbol used for flux density and the unit flux density the tesla (symbol T), commemorate the work the Croatian-born American physicist Nikola Tesla (1857–1943). Magnetic fields If permanent magnet placed surface and covered piece of paper, iron filings can shaken the paper from dispenser.13 and 5. Definition The places magnetic material where the lines flux are concen- trated are called the magnetic poles. 10. 9. 6. Lines magnetic flux never cross over each other. Definition Like poles repel; unlike poles attract. Lines magnetic flux travel along magnetic material and always emerge out the ‘north pole’ end the magnet. Gently tapping the paper then causes the filings take the shape the mag- netic field surrounding the permanent magnet.14. 8. These two statements are sometimes called the ‘first laws magnetism’ and are shown in Fig. Definition The region space through which the influence magnet can be detected called the magnetic field of that magnet. 7.Basic scientific concepts electrotechnology 113 3