1.1 An independent voltage source provides:
Correct Answer: a) A fixed voltage regardless of the current
Explanation: An ideal independent voltage source maintains a specified voltage across its terminals regardless of the current flowing through it. The voltage is fixed and doesn't depend on other circuit variables. Real voltage sources have some internal resistance causing voltage drop with increasing current.
1.2 A dependent source is controlled by:
Correct Answer: a) Another voltage or current in the circuit
Explanation: Dependent sources (also called controlled sources) have their voltage or current value determined by another voltage or current elsewhere in the circuit. There are four types: VCVS (voltage-controlled voltage source), CCVS (current-controlled voltage source), VCCS (voltage-controlled current source), and CCCS (current-controlled current source).
1.3 Which of the following is NOT a type of dependent source?
Correct Answer: c) Resistance-controlled current source (RCCS)
Explanation: The four standard types of dependent sources are all controlled by either voltage or current, not by resistance. The standard types are: 1. VCVS - Voltage Controlled Voltage Source 2. CCVS - Current Controlled Voltage Source 3. VCCS - Voltage Controlled Current Source 4. CCCS - Current Controlled Current Source
1.4 A practical voltage source consists of:
Correct Answer: a) An ideal voltage source in series with a resistor
Explanation: A practical voltage source is modeled as an ideal voltage source (with zero internal resistance) in series with a resistor representing the internal resistance. This internal resistance causes the terminal voltage to drop as current increases, which matches real-world behavior of voltage sources like batteries.
1.5 A dependent current source in a circuit is represented by:
Correct Answer: a) A diamond-shaped symbol
Explanation: In circuit diagrams, dependent (controlled) sources are represented by diamond-shaped symbols to distinguish them from independent sources (which use circular symbols). The diamond shape helps quickly identify that the source's value depends on another circuit variable.
2.1 In mesh analysis, the number of mesh equations required is equal to:
Correct Answer: a) The number of independent loops in the circuit
Explanation: Mesh analysis requires writing KVL equations for each independent mesh (loop) in the circuit. The number of independent meshes equals the number of window panes in the circuit (the holes in the circuit when drawn on paper). This is typically given by: Number of meshes = Number of branches - Number of nodes + 1.
2.2 The nodal analysis method is based on:
Correct Answer: a) Kirchhoff's Current Law (KCL)
Explanation: Nodal analysis is based on applying KCL at each principal node (except the reference node). It involves writing equations that sum the currents leaving each node to zero. The voltages at each node become the variables to solve for in the system of equations.
2.3 A supernode is formed when:
Correct Answer: a) A voltage source is connected between two non-reference nodes
Explanation: A supernode is created when a voltage source (dependent or independent) is connected between two non-reference nodes. The two nodes form a supernode, and we write a combined KCL equation for both nodes plus a constraint equation relating their voltages based on the voltage source.
2.4 If a circuit has 'N' nodes, the number of independent node equations needed in nodal analysis is:
Correct Answer: b) N - 1
Explanation: In nodal analysis, one node is selected as the reference node (usually ground), and voltages are measured relative to this reference. For N nodes, we need to write KCL equations at N-1 nodes (all nodes except the reference node). The reference node's voltage is defined as 0V.
2.5 Mesh analysis is preferred over nodal analysis when:
Correct Answer: d) The circuit has only voltage sources
Explanation: Mesh analysis is generally easier when: 1. The circuit has many series-connected elements 2. There are mostly voltage sources (as they fit naturally into KVL equations) 3. The circuit has fewer meshes than nodes Nodal analysis is typically easier when there are many parallel elements or current sources.