The number of lines in a unit area of a coil's magnetic field is defined as?

The term that describes the number of magnetic lines of force per unit area in a coil's magnetic field is known as flux density. It is typically measured in teslas (T) or webers per square meter (Wb/m²). Flux density indicates how strong the magnetic field is in a given area and reflects how much of the magnetic field is concentrated within that area. This is a critical concept in understanding electromagnetic principles, as it helps in assessing how effective a magnetic field will be in inducing currents in nearby conductors, or how it interacts within different materials.

Magnetic density, while somewhat related, is not the standard term used in this context and does not precisely define the phenomenon of magnetic lines per unit area. Magnetic coupling refers to the ability of one coil to influence another through magnetic fields, a different phenomenon altogether. Hysteresis density refers to the energy loss in a magnetic material due to its magnetization cycle and is not related to the concept of magnetic lines per unit area.