Electrical Engineering Midterm Vocabulary

Vocabulary flashcards covering core concepts, formulas, circuit laws, and measurement tools from Electrical Engineering Lectures 1 through 5.

Voltage ($V$)

Electrical potential difference or the 'push' that drives charge, measured in volts ($V$).

Current ($I$)

The rate of charge flow, measured in amperes ($A$); conventional current flows from positive ($+$) to negative ($-$) through a load.

Resistance ($R$)

Opposition to current flow, measured in ohms ($\Omega$); given by $R = \frac{\rho L}{A}$ for a uniform conductor.

Conductance ($G$)

The reciprocal of resistance, defined mathematically as $G = \frac{1}{R}$ and measured in siemens ($S$).

Power ($P$)

The rate of electrical energy transfer, measured in watts ($W$), expressed as $P = V I = I^2 R = \frac{V^2}{R}$.

Resistivity ($\rho$)

A material property measured in $\Omega \cdot m$ that directly determines a conductor's resistance in $R = \frac{\rho L}{A}$.

Ohm's Law

The mathematical relationship $V = I R$, which rearranges to $I = \frac{V}{R}$ and $R = \frac{V}{I}$.

Passive Sign Convention

The convention where current entering the terminal marked positive ($+$) of a resistor produces a voltage drop of $+I R$ when traveling in the assumed current direction.

Open Circuit

A condition with no conducting path, resulting in $I = 0$ and an effectively infinite resistance.

Short Circuit

An ideal zero-resistance path across which the voltage difference is $0\,V$.

Ammeter

A device connected in series within a branch to measure current, possessing an ideal internal resistance of $R_A \approx 0\,\Omega$.

Voltmeter

A device connected in parallel across a component to measure voltage, possessing an ideal internal resistance of $R_V \rightarrow \infty$.

Kirchhoff's Voltage Law (KVL)

The circuit law stating that $\sum V = 0$ around any closed loop.

Voltage Divider Rule

A formula calculating output voltage across resistor $R_2$ in series: $V_{\text{out}} = V_{\text{in}} \cdot \frac{R_2}{R_1 + R_2}$.

Kirchhoff's Current Law (KCL)

The circuit law stating that $\sum I_{\text{entering}} = \sum I_{\text{leaving}}$ at any electrical node.

Branch-Current Method

A technique for analyzing multi-loop circuits by assigning branch currents, applying KCL at nodes, and writing KVL equations for independent loops.