Basic Electrical Installation Work

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