Foundations — electrical power is defined as the rate of energy transfer (work per unit time), not as “how fast current is flowing.” Evaluate the statement.

Introduction / Context:
Power is one of the three pillars of Ohm’s law problems, alongside voltage and current. Misstatements such as “power measures how fast current flows” confuse learners and lead to dimensional errors. This item clarifies the physical meaning of electrical power and its correct formulas.

Given Data / Assumptions:

• Standard circuit quantities: voltage V, current I, resistance R.
• Time-average power in passive components; instantaneous definitions extend naturally.
• Ohmic behavior unless otherwise stated.

Concept / Approach:
Electrical power P is energy per unit time delivered to or drawn from a component. In lumped circuits, instantaneous power is p(t) = v(t) * i(t). For resistors under DC, P = V * I = I^2 * R = V^2 / R. None of these expressions measure “how fast current flows”; that idea is captured by current I itself (charge per unit time). Power tells you the rate at which electrical energy converts to heat, mechanical work, or other forms.

Step-by-Step Solution:

Verification / Alternative check:
Dimensional analysis: V (J/C) times I (C/s) yields J/s (watts). No “speed” quantity appears; current already equals charge per time, while power equals energy per time.

Why Other Options Are Wrong:

• Correct/only DC/depends solely on R/needs frequency: These distract from the fundamental definition P = V * I applicable across DC and AC.

Common Pitfalls:
Confusing current magnitude with power; forgetting that a high current at near-zero voltage can still imply low power (and vice versa).

Final Answer:
Incorrect — power is the rate of energy transfer, not the “speed” of current.