Car horns are simple electromagnetic devices that produce loud, audible sounds to get the attention of nearby vehicle occupants or pedestrians. A typical horn is composed of a magnetic coil, an armature with a metal diaphragm, a pair of electrical contacts, and a switch. When the driver activates the switch, the closed electric contact allows a current to flow through the coil generating a magnetic force that attracts the armature, as well as the metal diaphragm. This action breaks the electric contact, cutting off the current and releasing the armature and diaphragm. When they move back to their initial positions, the electrical contact is re-made and the cycle repeats. The rapid repetition of this process generates an oscillation of the diaphragm and creates the horn’s sound.