## 1. Kirchhoff's Current Law (KCL) states that:

### Answer:

### Explanation:

Kirchhoff's Current Law (KCL) is based on the conservation of charge and states that the total current entering a junction (or node) in a network equals the total current leaving that junction.

## 2. Ohm's Law relates which two electrical quantities?

### Answer:

### Explanation:

Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points. It is commonly formulated as V = IR, where V is voltage, I is current, and R is resistance.

## 3. In a DC circuit, resistors connected in series will have:

### Answer:

### Explanation:

In a series circuit, the same current flows through each resistor, but the voltage across each resistor can be different, depending on the resistance values.

## 4. The 'Thevenin's Theorem' is used to:

### Answer:

### Explanation:

Thevenin's Theorem simplifies a linear, bilateral network with any number of resistances and sources to a single voltage source and series resistance, making analysis easier.

## 5. Capacitive reactance in an AC circuit decreases with:

### Answer:

### Explanation:

Capacitive reactance (Xc) is inversely proportional to the frequency (f) of the AC signal, which means it decreases with an increase in frequency. Xc is given by 1/(2πfC), where C is capacitance.

## 6. Which law is used to analyze the flow of electric current in parallel circuits?

### Answer:

### Explanation:

Kirchhoff's Current Law (KCL) is used to analyze the flow of electric current in parallel circuits. It states that the total current entering a junction is equal to the total current leaving the junction.

## 7. In an AC circuit, inductive reactance increases with:

### Answer:

### Explanation:

Inductive reactance (Xl) is directly proportional to the frequency (f) of the AC signal. It increases with an increase in frequency and is given by Xl = 2πfL, where L is inductance.

## 8. 'Power factor' in AC circuits is defined as:

### Answer:

### Explanation:

Power factor in AC circuits is the ratio of real power (measured in watts) to apparent power (measured in volt-amperes). It indicates the efficiency of power usage, with a value ranging from 0 to 1.

## 9. A 'node' in an electrical circuit is:

### Answer:

### Explanation:

A node in an electrical circuit is a point where two or more components, such as resistors, capacitors, or inductors, are connected together. Nodes are essential points for analyzing circuits using network theories.

## 10. What is the main purpose of a 'transformer' in electrical circuits?

### Answer:

### Explanation:

The primary purpose of a transformer in electrical circuits is to change the voltage level, either stepping it up (increasing voltage) or stepping it down (decreasing voltage), while transferring electrical power from one circuit to another through electromagnetic induction.

## 11. A 'bilateral network' in electrical engineering is one in which:

### Answer:

### Explanation:

A bilateral network is characterized by its property that the current-voltage (I-V) relationship is the same in both directions of current flow. This means the behavior of the network remains unchanged when the direction of the source voltage is reversed.

## 12. 'Impedance' in AC circuits is:

### Answer:

### Explanation:

Impedance in AC circuits is a complex quantity that represents the total opposition to current flow, combining the effects of resistance, inductance, and capacitance.

## 13. Norton's Theorem states that any linear electric network with voltage and current sources and resistances can be replaced at terminals A-B by:

### Answer:

### Explanation:

Norton's Theorem is similar to Thevenin's Theorem and states that any two-terminal linear network can be simplified to an equivalent circuit consisting of a single current source in parallel with a single resistor.

## 14. Superposition theorem is used in electrical circuit analysis to:

### Answer:

### Explanation:

The superposition theorem states that in a linear circuit with multiple independent sources, the voltage across (or current through) an element is the algebraic sum of the voltages across (or currents through) that element caused by each independent source acting alone.

## 15. 'RMS value' of an AC voltage or current refers to:

### Answer:

### Explanation:

RMS (Root Mean Square) value of an AC voltage or current is a statistical measure of the magnitude of a varying quantity. It is particularly useful in electrical engineering because it gives the equivalent steady DC value that would deliver the same power to a load.

## 16. A 'ladder network' in electronics is composed of:

### Answer:

### Explanation:

A ladder network in electronics is a type of filter network typically composed of repeated units of series and parallel components (usually resistors and capacitors or resistors and inductors) arranged in a configuration resembling a ladder.

## 17. In network analysis, 'mesh analysis' is used to:

### Answer:

### Explanation:

Mesh analysis, also known as loop analysis, is a method used in network theory to calculate the current in each mesh (independent loop) of a circuit. It is based on Kirchhoff's Voltage Law.

## 18. 'Maximum Power Transfer Theorem' is used to determine:

### Answer:

### Explanation:

The Maximum Power Transfer Theorem states that to obtain the maximum external power from a source with a finite internal resistance, the resistance of the load must equal the resistance of the source.

## 19. 'Phase margin' in network analysis is a measure of:

### Answer:

### Explanation:

Phase margin is a measure of system stability used in control theory and signal processing. It indicates how far the system is from the point of instability in the frequency domain.

## 20. A 'Y-Δ transformation' is used in circuit analysis to:

### Answer:

### Explanation:

Y-Δ transformation (also known as star-delta transformation) is used to simplify the analysis of circuits by converting a three-terminal Y (star) network to an equivalent Δ (delta) network and vice versa.

## 21. A 'voltage divider' circuit is used to:

### Answer:

### Explanation:

A voltage divider is a simple circuit that turns a large voltage into a smaller one using two resistors. The output voltage of a voltage divider is a fraction of its input voltage.

## 22. In AC circuit analysis, 'reactance' is:

### Answer:

### Explanation:

Reactance is the opposition offered by a capacitor or inductor to the change of current in an AC circuit. It is frequency-dependent, with capacitive reactance decreasing and inductive reactance increasing with frequency.

## 23. The principle of 'duality' in network theory states that:

### Answer:

### Explanation:

The principle of duality in network theory states that every network has a corresponding dual in which series and parallel connections, as well as voltage and current sources, are interchanged while maintaining the network's behavior.

## 24. A 'Zener diode' in a circuit is typically used for:

### Answer:

### Explanation:

A Zener diode is designed to operate in the reverse breakdown region and is commonly used for voltage regulation, as it maintains a constant voltage across itself when the voltage across it exceeds its Zener breakdown voltage.

## 25. In electrical circuits, 'Power Factor Correction' is used to:

### Answer:

### Explanation:

Power Factor Correction (PFC) is used to improve the power factor in electrical circuits, which is achieved by aligning the phase of voltage and current. This reduces the apparent power (VA) in the circuit, making the power system more efficient.