Basic Electrical Installation Work

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this, think the current being repre- sented dart arrow inside the conductor.15(a), the magnetic field would spiralling anticlockwise around the conductor. Imagine corkscrew screw being turned that will move the direction the current. The dot represents current coming towards when would see the point the arrow dart inside the conductor. 5.Basic Electrical Installation Work 114 Electromagnetism Electricity and magnetism have been inseparably connected since the experiments Oersted and Faraday the early nineteenth century.15 and its direction can determined the ‘dot’ ‘cross’ nota- tion and the ‘screw rule’. Therefore, if the current was coming out the paper, shown Fig.15(b), the mag- netic field would spiral clockwise around the conductor. . The cross represents current going away from when we would see the flights the dart arrow. N S N S S N Like poles repel Unlike poles attract FIGURE 5. 5. An electric current flowing conductor produces magnetic field ‘around’ the conductor which proportional the current. 5. If the current was going into the paper, shown Fig. Thus small current produces weak magnetic field, while large current will produce strong magnetic field.14 The first laws magnetism. The magnetic field ‘spirals’ around the conductor, shown in Fig