Q

QuestionElectrical Engineering & Electronics

The problem describes a method to detect the presence of a magnetic field in a given region of space using a coil of wire carrying an electric current. The method involves fixing the axis of the coil and rotating the coil's plane in the space. If the coil does not experience any torque while rotating, then there is no magnetic field present at that location. However, if the coil experiences a torque while rotating, then there is a magnetic field present at that location.

The principle behind this method is based on the interaction between magnetic fields and electric currents. A magnetic field exerts a force on a moving charge, which is perpendicular to both the magnetic field and the velocity of the charge. This force is given by F = qvBsinθ, where F is the force, q is the charge, v is the velocity, B is the magnetic field, and θ is the angle between the magnetic field and the velocity. In the case of a coil of wire carrying an electric current, the magnetic field exerts a torque on the coil, which tends to align the coil with the magnetic field. The torque is given by τ = NIABsinθ, where τ is the torque, N is the number of turns in the coil, I is the current, A is the area of the coil, B is the magnetic field, and θ is the angle between the magnetic field and the normal to the coil's plane.