BEE Bachelor of Electrical Engineering Fundamental Circuit Analysis Questions and Answers

Question 1

According to Kirchhoff's Current Law (KCL), what is the fundamental principle governing the flow of current at any node (junction) in an electrical circuit?

Accepted Answer

The algebraic sum of currents entering and leaving the node is zero.

Answer

Kirchhoff's Current Law is based on the principle of conservation of charge. It states that because charge cannot accumulate at a node, the total amount of current flowing into a node must be equal to the total amount of current flowing out of it. Therefore, the algebraic sum of all currents entering and leaving the node must be zero.

Question 2

In a DC circuit, a 10V source is connected to a series combination of a 3Ω resistor and a 2Ω resistor. What is the power dissipated by the 3Ω resistor?

Accepted Answer

12 W

Answer

First, calculate the total resistance (Req) of the series circuit: Req = R1 + R2 = 3Ω + 2Ω = 5Ω. Next, use Ohm's Law to find the total current (I) flowing through the circuit: I = V / Req = 10V / 5Ω = 2A. Since the resistors are in series, the same current flows through both. Finally, calculate the power (P) dissipated by the 3Ω resistor using the formula P = I²R: P = (2A)² * 3Ω = 4 * 3 = 12 W.

Question 3

Which of the following statements is true regarding a capacitor in a DC circuit after it has been fully charged?

Accepted Answer

It acts as an open circuit.

Answer

When a capacitor is connected to a DC source, it charges up. Once fully charged, the voltage across the capacitor equals the source voltage. At this point, the capacitor opposes any further flow of DC current, effectively behaving like an open circuit. No more current flows through the capacitor branch.

Question 4

A circuit designer needs to find a simplified equivalent circuit for a complex linear network. The equivalent circuit should consist of a single voltage source and a single series resistor. Which theorem should be applied?

Accepted Answer

Thevenin's Theorem

Answer

Thevenin's theorem states that any two-terminal linear electrical network can be replaced by an equivalent circuit composed of a single voltage source (Vth) in series with a single resistor (Rth). This is precisely what the scenario describes.

Question 5

For maximum power to be transferred from a DC voltage source with an internal resistance (Rs) to a connected load resistance (RL), what must be the relationship between the resistances?

Accepted Answer

RL must be equal to Rs.

Answer

The Maximum Power Transfer Theorem states that for a DC circuit, the maximum power is delivered to the load resistor (RL) when the load resistance is equal to the Thevenin equivalent resistance of the source (Rth), which in this case is the internal resistance (Rs).

BEE - Bachelor of Electrical Engineering Practice Test

BEE - Bachelor of Electrical Engineering Practice Test

BEE Bachelor of Electrical Engineering Fundamental Circuit Analysis Questions and Answers