Hall effect geometry: in a standard Hall-effect sensor, the magnetic field (B), the current through the Hall element (I), and the measured Hall voltage (V_H) are mutually orthogonal (each at right angles to the other). Assess this statement.

Introduction / Context:
The Hall effect underpins magnetic field sensors and current probes. Understanding the orientation of the magnetic field, current, and Hall voltage is crucial for correct device mounting and signal interpretation.

Given Data / Assumptions:

• A rectangular Hall plate carries current along one axis.
• A magnetic field is applied perpendicular to the current path.
• Charge carriers experience the Lorentz force and accumulate on the sides, producing a transverse voltage.

Concept / Approach:
In the Hall effect, carriers with drift velocity v_d moving in magnetic field B experience a force q*(v_d × B). This deflects carriers sideways, creating a transverse electric field and hence a measurable Hall voltage across the plate. The canonical setup has: current along x, magnetic flux density along z, and Hall voltage along y, making the three directions mutually orthogonal.

Step-by-Step Solution:

Verification / Alternative check:
Swapping the sign of B reverses the polarity of V_H. Rotating the sensor so that B is parallel to current collapses V_H to near zero, confirming the cross-product geometry.

Why Other Options Are Wrong:
Incorrect: contradicts the fundamental Hall geometry.

True only for semiconductors or only for alternating fields: the orthogonality requirement is geometric and applies broadly; semiconductors are preferred for sensitivity, not for geometry.

Common Pitfalls:
Mounting a sensor with the wrong orientation; mixing up lead designations; expecting Hall voltage when B is parallel to current (it is maximized when perpendicular).

Final Answer:
Correct