A metal detector is an electronic device that detects the presence of metal. It is used for security purposes, to find buried treasure, and to locate metal objects in the ground. Metal detectors work by using a coil to create a magnetic field. When metal is present, it distorts the magnetic field, which is detected by the coil. The detector then emits a signal to indicate the presence of metal.
Metal detectors have been used for centuries to find buried treasure. In the early days, metal detectors were simple devices that consisted of a coil and a battery. Modern metal detectors are much more sophisticated and can detect metal objects at great depths. Metal detectors are also used for security purposes, such as at airports and government buildings. They can be used to detect weapons, explosives, and other dangerous objects.