Final answer:
A moving electric charge, a permanent magnet, and a current-carrying wire all produce magnetic fields. Non-magnetic materials under normal conditions do not generate magnetic fields.
Step-by-step explanation:
Magnetic fields are related to electric charges in motion. In physics, one of the fundamental principles is that a moving electric charge or a current-carrying wire will produce a magnetic field. When we talk about a current-carrying wire, it implies that there are moving electric charges within that wire. Our everyday electronics and electrical systems operate based on this principle. Magnetic fields are invisible force fields that can act on ferromagnetic materials or moving electric charges.
A permanent magnet, often made of materials like iron, nickel, or cobalt, will naturally produce a magnetic field due to the alignment of the atomic dipoles within the material. This field is always present, regardless of external influences. On the other hand, a moving electric charge, such as an electron flowing through a wire, generates a magnetic field around the wire. This phenomenon is described by Maxwell's equations and is fundamental to the operation of many electrical devices.
However, non-magnetic materials do not create a magnetic field when subjected to standard conditions, as their atomic dipoles do not align in a way to produce a net magnetic field. A steady current in a DC circuit will not produce electromagnetic waves, but if there is a change in the magnitude of the current (for example, turning it on or off), then electromagnetic waves are emitted.
Therefore, the entities that will create a magnetic field are a moving electric charge, a permanent magnet, and a current-carrying wire.