What kind of field is created by a moving charge?

• A. Electric field
• B. Magnetic field
• C. Gravitational field
• D. Electromagnetic field

Answer: (B)

A moving charge creates a magnetic field due to its motion. When electric charges are at rest, they produce an electric field around them; however, when they are in motion, they generate magnetic fields as a result of the relativistic effects described by electromagnetic theory. This phenomenon is a fundamental tenet of electromagnetism, where the motion of charged particles leads to the magnetic interaction, which is observed in scenarios such as current flowing through a wire or a charged particle moving through space.

The relationship between electric and magnetic fields is established by Maxwell's equations, which describe how changing electric fields can produce magnetic fields and vice versa. It’s important to note that while all charges create electric fields, only those that are moving create magnetic fields. Thus, the answer correctly identifies that a moving charge specifically produces a magnetic field.