BEE Electric Circuits 4

Question 1

A circuit has an impedance Z = 3 + j4 Ω. What is the magnitude of the impedance?

Accepted Answer

5 Ω

Answer

|Z| = √(3² + 4²) = √(9 + 16) = √25 = 5 Ω.

Question 2

In mesh analysis, a mesh current is defined as a current flowing:

Accepted Answer

Around a single closed loop (mesh) of the circuit

Answer

Mesh analysis assigns a circulating current variable to each independent mesh (window pane) in the circuit.

Question 3

What happens to the capacitive reactance XC as frequency increases?

Accepted Answer

XC decreases

Answer

Capacitive reactance XC = 1/(2πfC), so as frequency increases, XC decreases.

Question 4

Which theorem states that maximum power is transferred to a load when the load resistance equals the source's Thevenin resistance?

Accepted Answer

Maximum Power Transfer Theorem

Answer

The Maximum Power Transfer Theorem states that PL is maximum when RL = Rth.

Question 5

The quality factor Q of a series RLC circuit is defined as:

Accepted Answer

ω₀L / R

Answer

For a series RLC circuit, Q = ω₀L/R = 1/(ω₀CR), representing the ratio of stored to dissipated energy.

BEE - Bachelor of Electrical Engineering Practice Test