ISCET AC Circuits and Analysis 4

Question 1

When analyzing AC circuits using phasors, inductive impedance is represented as:

Accepted Answer

+jXL

Answer

Inductive impedance is ZL = +jXL = jωL, placing it on the positive imaginary axis in the complex plane.

Question 2

If an AC circuit has a power factor of 0.6 lagging and apparent power of 100 VA, what is the true power?

Accepted Answer

60 W

Answer

True power P = S × PF = 100 VA × 0.6 = 60 W.

Question 3

Which of the following best describes 'leading' power factor?

Accepted Answer

Current leads voltage, caused by capacitive loads

Answer

A leading power factor means current leads voltage, which occurs in circuits where capacitive reactance dominates.

Question 4

The bandwidth of a series resonant circuit with fr = 500 kHz and Q = 50 is:

Accepted Answer

10 kHz

Answer

BW = fr/Q = 500 kHz / 50 = 10 kHz.

Question 5

In a transformer, the secondary current compared to the primary current is determined by:

Accepted Answer

The inverse of the turns ratio

Answer

Current transforms inversely to voltage: Is/Ip = Np/Ns, the inverse of the voltage turns ratio.

(ISCET) International Society of Certified Electronics Technicians Practice Test