Power fundamentals: Choose the best definition of electrical power in physics and electronics.

Introduction / Context:
Power connects energy and time. In circuits it determines heating, sizing of supplies, and efficiency. Knowing the correct definition helps relate formulas like P = V * I and P = I^2 * R back to physical meaning.

Given Data / Assumptions:

• Standard physics definitions.
• Energy measured in joules (J), time in seconds (s), power in watts (W).
• Electrical work equals charge moved times potential difference.

Concept / Approach:
Power is the time rate of doing work or transferring energy. Mathematically: P = dW/dt or P = dE/dt. In steady DC circuits, it reduces to algebraic forms like P = V * I because work per unit charge is V and charge per unit time is I.

Step-by-Step Solution:

Verification / Alternative check:
Unit analysis: V * A = (J/C) * (C/s) = J/s = W, confirming consistency.

Why Other Options Are Wrong:

• Work: That is energy, not its time rate.
• Conversion of energy: Too vague; power quantifies the rate of conversion.
• Joules: A unit of energy, not power.

Common Pitfalls:
Confusing energy with power; using watt-hours (energy) when watts (power) are intended.

Final Answer:
the rate at which work is done