SACE Stage 2 Physics Practice Exam

Magnetic flux is measured in Webers. This unit is derived from the fundamental definitions of magnetic field strength and the area through which the magnetic field lines pass. Specifically, one Weber represents the total magnetic flux that passes through a surface of one square meter in a magnetic field of one Tesla.

Understanding magnetic flux requires recognizing that it is the product of the magnetic field and the area through which the field lines intersect, factoring in the angle between the magnetic field direction and the normal to the surface. Therefore, the Weber effectively quantifies how much magnetic field is 'flowing' through a given area, making it the standard unit for measuring this physical quantity.

Other options represent different physical quantities: voltage (Volt) relates to electric potential, energy (Joule) measures work or energy transfer, and magnetic field strength is conveyed in Teslas. Each of these units is integral to the understanding of electromagnetism, but only the Weber specifically quantifies magnetic flux.