A galvanometer is an instrument used to detect and measure small electrical currents. It works by using a coil of wire suspended in a magnetic field, which experiences a torque when a current passes through it.
A galvanometer consists of a coil of wire, a magnet, and a pointer. When a current passes through the coil, it creates a magnetic field that interacts with the magnetic field of the permanent magnet. This interaction causes the coil to rotate, which moves the pointer along a scale to indicate the strength and direction of the current.
The sensitivity of a galvanometer refers to its ability to detect and measure small changes in current. It is typically measured in microamperes per division, with higher sensitivity indicating the ability to detect smaller changes in current.
The current sensitivity of a galvanometer is determined by its design, specifically the strength of the magnetic field, the number of turns in the coil, and the type of suspension used for the coil. These factors affect the amount of torque the coil experiences and, therefore, its ability to detect small changes in current.
The sensitivity of a galvanometer can be increased by increasing the strength of the magnetic field, increasing the number of turns in the coil, or using a more sensitive suspension for the coil. Additionally, using a higher quality instrument with less friction and better calibration can also improve sensitivity.