Magnetization (B–H) characteristic: On a standard B–H curve used in electrical engineering materials, which two physical quantities are plotted on the horizontal and vertical axes, respectively?

Introduction / Context:
The B–H curve is a foundational graph in electromagnetism and magnetic materials. It captures how a material’s magnetic flux density responds to an applied magnetizing force. This relationship underpins transformer core design, inductor sizing, saturation analysis, and hysteresis loss estimation, making it essential knowledge for electrical and electronics engineers.

Given Data / Assumptions:

• B represents magnetic flux density, typically measured in tesla (T) or weber per square meter (Wb/m^2).
• H represents magnetizing force (magnetic field intensity), typically in ampere-turns per meter (A·turn/m or A/m).
• The standard graph places H on the horizontal axis and B on the vertical axis.
• We consider generic ferromagnetic material behavior, including possible hysteresis when cycled.

Concept / Approach:
Flux density B quantifies how much magnetic flux per unit area is established within the material. Magnetizing force H quantifies the effort applied by currents (ampere-turns) to magnetize the material. Plotting B versus H shows key phenomena: initial magnetization, knee of the curve (onset of saturation), and the closed hysteresis loop under alternating excitation which indicates core loss.

Step-by-Step Solution:
Identify the axes: B on the vertical axis and H on the horizontal axis.Interpretation: as H increases, B increases nonlinearly, approaching saturation.Under AC cycling, the path forms a loop (hysteresis), whose enclosed area equals hysteresis energy loss per cycle.Therefore, the two plotted quantities are flux density (B) and magnetizing force (H).

Verification / Alternative check:
Standard transformer and inductor textbooks show B–H plots with H along x-axis and B along y-axis. Laboratory B–H tracers also output B vs H directly, confirming the convention.

Why Other Options Are Wrong:
Reluctance/permeability are material parameters, not the direct plotted axes.Magnetizing force and permeability: permeability is a slope (dB/dH) or ratio B/H, not an axis quantity.

Common Pitfalls:
Confusing B–H with the B versus time or H versus time plots. Also, note that permeability varies with H; it is not constant across the whole curve.

Final Answer:
flux density and magnetizing force