Basic concept check: Does electrical resistance limit or oppose the flow of current in a circuit?

Introduction / Context:
Resistance is one of the three primary electrical quantities along with voltage and current. Understanding its role is essential for designing safe and functional circuits.

Given Data / Assumptions:

• Ohm’s law applies: V = I * R.
• Linear resistive behavior (no significant temperature or nonlinearity effects).
• Either DC or AC conditions at frequencies where resistive behavior dominates.

Concept / Approach:
For a given applied voltage, the current through a resistor is I = V / R. A larger R yields smaller I, demonstrating that resistance limits current. Physically, resistance converts electrical energy into heat (I^2R losses), representing opposition to charge flow due to collisions within the material lattice.

Step-by-Step Solution:

Verification / Alternative check:
Measure a simple circuit: a fixed 9 V source with resistors of 100 Ω and 1 kΩ yields 90 mA and 9 mA respectively, confirming current is limited by resistance.

Why Other Options Are Wrong:

• “Resistance increases current” (option b) inverts the relationship.
• “Resistance stores energy” (option c) confuses resistors with capacitors/inductors.
• “Only affects AC” (option d) is incorrect; Ohm’s law holds for DC as well.

Common Pitfalls:
Confusing resistance (opposition with dissipation) with reactance (opposition with energy storage). Both oppose current but in different ways.

Final Answer:
Yes — resistance limits current.