A galvanometer is an instrument used to detect and measure small electric currents in a circuit. Its purpose is to indicate the presence, direction, and magnitude of current flow in a circuit.
A small/cheap galvanometer is needed for experiments or projects where precise measurements of small electric currents are required, but a more expensive and larger galvanometer is not necessary. It is also useful for those on a budget.
A galvanometer works by using the principle of electromagnetism. A current is passed through a coil of wire, which creates a magnetic field. When a current is passed through the circuit being measured, it interacts with the magnetic field and causes the coil to move. This movement is then translated into a reading on a scale.
There are several types of galvanometers, including moving coil, moving magnet, and mirror galvanometers. Moving coil galvanometers are the most common and use a coil of wire suspended in a magnetic field. Moving magnet galvanometers have a permanent magnet that moves the coil, while mirror galvanometers use a mirror attached to the coil to reflect a beam of light onto a scale for measurement.
Galvanometers have a wide range of applications, including in scientific experiments, electrical testing, and telecommunications. They are also used in medical equipment, such as electrocardiograms, to measure the electrical activity of the heart. In addition, galvanometers are used in various industrial and manufacturing processes to monitor and control electrical currents.