Ohm's law defines the fundamental relationship among which three electrical quantities used in circuit analysis and design?

Introduction:
Ohm's law is the cornerstone of basic circuit theory. It relates voltage (the electrical potential difference), current (the rate of charge flow), and resistance (opposition to current) with a simple proportionality used in virtually every DC and many AC calculations.

Given Data / Assumptions:

• Applies to ohmic (linear) resistive elements over the operating region of interest.
• Ambient conditions and temperature kept within normal ranges where resistance is approximately constant.

Concept / Approach:
The relationship is V = I * R. If any two of the quantities are known, the third can be solved directly. This enables sizing of resistors, predicting currents, or determining safe supply voltages.

Step-by-Step Solution:
Start from V = I * RSolve for current: I = V / RSolve for resistance: R = V / IApply proportionality: doubling V at fixed R doubles I; doubling R at fixed V halves I.

Verification / Alternative check:
Lab measurements with a resistor and variable DC supply show linear I–V plots passing through the origin, confirming the proportionality embodied in Ohm's law.

Why Other Options Are Wrong:

• voltage, current, and time / resistance, time, and current: Time is not part of the Ohm's law identity.
• power, current, and resistance: Power relates via P = V * I = I^2 * R = V^2 / R, which derives from Ohm's law but is not the law itself.
• charge, flux, and inductance: These relate to other electromagnetic concepts, not Ohm's law.

Common Pitfalls:

• Applying Ohm's law to non-linear devices (diodes, lamps) where V–I is not linear.
• Ignoring temperature effects that change R significantly in some materials.

Final Answer:
voltage, current, and resistance