Measurement reference — definition of ground: In practical electronic circuits, “ground” (or reference) is the node against which all other voltages are measured. Decide whether this statement accurately describes ground.

Introduction / Context:
Voltage is inherently a difference in electric potential between two points. To report a single number for “the voltage” at a node, engineers choose a reference node—commonly called ground (GND). Understanding that ground is a reference, not always literally the Earth, is essential for measurement, safety, and PCB design.

Given Data / Assumptions:

• Ground refers to the designated reference node in the circuit schematic.
• Measuring instruments report V_node = V(node) - V(ground).
• Earth bonding may or may not be used depending on system class.

Concept / Approach:
Ground provides a common return path and a reference potential for signals and supplies. In many systems there are multiple grounds (analog, digital, chassis) that are tied at a single point. Whether connected to Earth or not, the chosen ground serves as the zero-volt reference for measurements and specifications throughout the circuit.

Step-by-Step Solution:

Verification / Alternative check:
Oscilloscope probes and DMMs default to ground-referenced measurements; datasheets specify output “with respect to GND,” confirming the definition in practice.

Why Other Options Are Wrong:

• Incorrect: Ground is indeed the reference node by definition.
• True only for earth-grounded systems / AC power circuits / metal chassis: Ground as a reference applies irrespective of earthing method or enclosure material.

Common Pitfalls:
Assuming ground always equals Earth potential; mixing up safety ground, chassis ground, and signal return; creating ground loops by multiple bonding points.

Final Answer:
Correct