In a typical moving-coil galvanometer, the wire loop (also known as the coil) can turn through a limited angle when electric current flows through it. The maximum angle of rotation depends on several factors, including the strength of the magnetic field, the number of turns in the coil, the current passing through the coil, and the restoring torque provided by the suspension system.

Here are some factors that determine the angle of rotation of the wire loop in a galvanometer:

1. Strength of Magnetic Field: The stronger the magnetic field, the greater the torque experienced by the coil. A stronger magnetic field exerts a higher force on the current-carrying conductors in the coil, causing the coil to rotate more freely.

2. Number of Turns in the Coil: The more turns the coil has, the greater the magnetic field it creates and the more sensitive the galvanometer becomes. Each additional turn contributes to the overall magnetic moment of the coil, increasing the torque produced by the magnetic field.

3. Electric Current: The amount of current flowing through the coil directly influences the angle of rotation. The greater the current, the stronger the magnetic field generated by the coil, and consequently, the larger the deflection angle.

4. Restoring Torque: The suspension system of the galvanometer provides a restoring torque that opposes the rotation of the coil. The restoring torque is typically created by a spring or a torsion wire. When the coil deflects from its equilibrium position, the restoring torque acts to bring it back to the zero position.

The angle of rotation of the wire loop is directly proportional to the current flowing through the coil and inversely proportional to the restoring torque. As a result, the galvanometer can accurately measure small changes in electric current by observing the angle of rotation of the coil.