Hysteresis meaning: Hysteresis is not a measure of lines of force per unit area; it describes the lagging relationship between B and H in a magnetic material (the hysteresis loop). True or false?

Introduction / Context:
This item distinguishes between magnetic flux density and hysteresis. Misdefining hysteresis leads to incorrect interpretations of core losses and material selection for magnetic components.

Given Data / Assumptions:

• Flux density B is flux per unit area (measured in tesla).
• Hysteresis describes the path-dependent relationship between B and H.
• The hysteresis loop area quantifies hysteresis loss per cycle.

Concept / Approach:

“Number of lines of force per unit area” corresponds to flux density B, not hysteresis. Hysteresis refers to the lag (history dependence) in magnetic response: when H cycles, B follows a loop due to domain dynamics, causing energy loss and residual magnetization (retentivity).

Step-by-Step Solution:

Verification / Alternative check:

Observe B–H curves from material datasheets. The loop demonstrates hysteresis; separate measurements of B (tesla) concern field intensity and geometry, not hysteresis alone.

Why Other Options Are Wrong:

• Choosing “True” would redefine hysteresis incorrectly and obscure the cause of magnetic core losses and remanence.

Common Pitfalls:

Equating lines-of-force visuals with quantitative B; overlooking that hysteresis depends on material microstructure and frequency, while B depends on instantaneous field and geometry.

Final Answer:

False