Cite a Poem From a Book. EasyBib can help you cite a poem from a book, here's how: 1  Type in the ISBN of your text book (find inside the front of the book).  If more than one book is listed, double check the details and click Select on the correct book.
Without electromagnets, the speakers won't work, that is why they are used. Like asking why an engine is used in an automobile, or blades in a fan. Some speakers do you electrostatics to produce the motion needed to produce sound. billrussell42 Â· 7 years ago. Thumbs up. 1.here is an electromagnet attatched to the diaphragm. When current flows through the coil one way it becomes a magnet. since there is a permanent magnet behind the coil, the coil is pulled toward the magnet.
An electromagnet works on the principle that an electric current not only allows electrons to flow in a circuit, but also generates a small magnetic field. When a wire carrying electricity is coiled, the magnetic field becomes even stronger. Iron or steel objects surrounded by this coiled electric wire also become magnetized. This combination of electronic energy, coiled wiring and conductive metal object forms the basis of the device. It may be easier to think of an electromagnet as an electron magnet, not an electric magnet. What is relevant is the free flow of electrons in a circuit and their effects on the wire carrying them. It's possible to demonstrate the basic principles using a supply of bare copper wiring, a D-size chemical battery, and an iron or steel nail.