The correct answer is: B. Current is induced in a conductor that is moving through a magnetic field.
A generator is a device that converts mechanical energy into electrical energy. The basic principle of a generator is that when a conductor moves through a magnetic field, an electric current is induced in the conductor. This is known as Faraday’s law of induction.
The amount of current induced in the conductor depends on the strength of the magnetic field, the speed of the conductor through the field, and the length of the conductor in the field.
Generators are used in a variety of applications, including power generation, welding, and medical imaging.
Option A is incorrect because it describes the basic principle of a motor, not a generator. In a motor, a current is passed through a conductor that is located in a magnetic field. This causes the conductor to experience a force, which causes it to rotate.
Option C is incorrect because it describes the basic principle of a magnet, not a generator. In a magnet, the magnetic field is created by the alignment of the magnetic domains in the material.
Option D is incorrect because it describes the basic principle of an electromagnet, not a generator. In an electromagnet, a current is passed through a conductor that is wrapped around a core. This creates a magnetic field around the core.
Option E is incorrect because it is not one of the basic principles of a generator.