Electrical measurements: Resistance is measured in which unit in the International System of Units (SI)?

Introduction / Context:
Understanding base electrical units is foundational for anyone working with circuits. Resistance quantifies how strongly a component opposes the flow of electric current.

Given Data / Assumptions:

• We seek the unit of resistance, not of current, voltage, or capacitance.
• SI units and standard electrical terminology are expected.

Concept / Approach:

Ohm’s law relates voltage (V), current (I), and resistance (R) by V = I * R. Rearranging shows that resistance equals voltage divided by current. The SI unit is therefore volt per ampere, named the ohm (symbol Ω). Digital multimeters display resistance directly in ohms, kilo-ohms, or mega-ohms depending on the magnitude.

Step-by-Step Solution:

Verification / Alternative check:

Instrument manuals and component datasheets list resistive values in Ω, kΩ, or MΩ, confirming the standard.

Why Other Options Are Wrong:

• Farads: Capacitance.
• Helids: Not an electrical unit.
• Amperes: Current.
• Volts: Voltage.

Common Pitfalls:

Misreading resistor color codes; confusing kilo-ohms and mega-ohms; measuring resistance in-circuit while other paths distort readings.

Final Answer:

ohms