# MCQ in Electrical Circuit Part 9 | ECE Board Exam

(Last Updated On: November 24, 2020) This is the Multiples Choice Questions Part 9 of the Series in Electrical Circuit as one of the Electronics Engineering topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electronics Engineering field, Electronics Books, Journals and other Electronics References.

#### MCQ Topic Outline included in ECE Board Exam Syllabi

• MCQ in AC-DC circuits
• MCQ in Resistors
• MCQ in Inductors
• MCQ in Capacitors

#### Continue Practice Exam Test Questions Part 9 of the Series

Choose the letter of the best answer in each questions.

401. A 100-volt source is supplying a parallel RC circuit having a total impedance of 35.35 Ω. Calculate the total line current.

A. 2.83 ∠ 45°

B. 2.83 ∠ -45°

C. 4.00 ∠ 45°

D. 4.00 ∠ -45°

Solution:

402. What is the power factor of a circuit if the inductive susceptance and conductance have the same value?

A. 0.325

B. 0.525

C. 0.673

D. 0.707

Solution:

403. If a circuit has an admittance of Y = 0.2 + j0.6, the circuit is

A. purely inductive

B. inductive

C. capacitive

D. reactive

Solution:

404. The circuit admittance Y = 0.2 – j0.6, the circuit is

A. resistive

B. inductive

C. capacitive

D. reactive

Solution:

405. What is the resonant frequency of a circuit when L is 50 microhenrys and C is 40 picofarads are in parallel?

A. 7.96 MHz

B. 79.6 MHz

C. 3.56 MHz

D. 1.78 MHz

Solution:

406. If you need an LC circuit to be resonant at 2500 Hz and use a 150 mH coil, what should the capacitance value be?

A. 0.027 μF

B. 0.015 μF

C. 0.15 μF

D. 27 μF

Solution:

407. What is the resonant frequency of a circuit when L of 3 microhenry and C of 40 picofarad are in series?

A. 1.33 MHz

B. 14.5 MHz

C. 14.5 kHz

D. 1.33 kHz

Solution:

408. What is the resonant frequency of a circuit when L of 25 microhenry and C of 10 picofarad are in parallel?

A. 63.7 MHz

B. 10.1 MHz

C. 63.7 kHz

D. 10.1 kHz

Solution:

409. A series circuit at resonance would mean, the circuit is

A. resistive

B. inductive

C. capacitive

D. reactive

Solution:

410. Characteristics of the current in a series R-L-C circuit at resonance.

A. It is dc

B. It is a minimum

C. It is zero

D. It is at maximum

Solution:

411. What is the cause of a minimum Q on a single-tuned LC circuit?

A. decreased series resistor

B. decreased shunt resistor

C. increased shunt resistor

D. decreased capacitance

Solution:

412. Find the half-power bandwidth of a parallel resonant circuit, which has a resonant frequency of 3.6 MHz and a Q of 218.

A. 606 kHz

B. 58.7 kHz

C. 16.5 kHz

D. 47.3 kHz

Solution:

413. A parallel circuit at resonance would mean, the circuit is

A. resistive

B. inductive

C. reactive

D. capacitive

Solution:

414. What will happen to a parallel ac-circuit if its line frequency is more than the resonant frequency?

A. becomes purely resistive

B. becomes purely capacitive

C. becomes inductive

D. becomes capacitive

Solution:

415. In a series ac-circuit, if the line frequency is more than the resonant frequency, the circuit behaves as

A. resistive

B. inductive

C. reactive

D. capacitive

Solution:

416. If the line frequency of a parallel ac-circuit is less than the resonant frequency, the circuit behaves as

A. resistive

B. reactive

C. capacitive

D. purely inductive

Solution:

417. If an ac-series circuit is supplied with a source whose frequency is less than that of fr, the circuit becomes

A. resistive

B. reactive

C. inductive

D. capacitive

Solution:

418. _________ is a parallel LC circuit.

A. Parallel resisting circuit

B. Static circuit

C. Tank circuit

D. Hartley circuit

Solution:

419. A parallel LC network with L = 100 mH and C = 25 μF will resonate at what frequency?

A. 25 Hz

B. 45.5 Hz

C. 75.6 Hz

D. 100 Hz

Solution:

420. Absolutely, when can we say that the circuit is at resonance?

A. when XL = XC

B. when the current is minimum

C. when the voltage and current are in-phase

D. all of the above

Solution:

421. The description of two sine waves that are in step with each other going through their maximum and minimum points ate the same time and in the same direction.

A. Sine waves in phase

B. Stepped sine waves

C. Phased sine waves

D. Sine waves in coordination

Solution:

422. Term used for the out of phase, non-productive power associated with inductors and capacitors.

A. Effective power

B. True power

C. Reactive power

D. Peak envelope power

Solution:

423. Refers to a reactive power.

A. Wattles, non productive power

B. Power consumed in circuit Q

C. Power loss because of capacitor leakage

D. Power consumed in wire resistance in an inductor

Solution:

424. A 240 V, 25 Hz sinusoidal generator is connected to a 20 ohms resistor. Determine the instantaneous current when elapsed time is 0.01 second.

A. 15043A

B. 16.30 A

C. 16.97 A

D. 12.00 A

Solution:

425. The product of current and voltage in an AC circuit refers to the

A. Real power

B. Useful power

C. Apparent power

D. DC power

Solution:

426. The distance covered or traveled by a waveform during the time interval of one complete cycle.

A. Frequency

B. Wavelength

C. Time slot

D. Wave time

Solution:

427. The power dissipated across the resistance in an AC circuit.

A. Real power

B. Reactive power

C. Apparent power

D. True power

Solution:

428. It is the number of complete cycles of alternating voltage or current complete each second

A. Period

B. Frequency

C. Amplitude

D. Phase

Solution:

429. How many degrees are there in one complete cycle?

A. 720 deg

B. 360 deg

C. 180 deg

D. 90 deg

Solution:

430. The impedance in the study of electronics is represented by resistance and _________ .

A. Reactance

B. Inductance and capacitance

C. Inductance

D. capacitance

Solution:

431. Two current sources deliver to a common load. The first source delivers current whose equation is 25sin 100πt A while the second delivers a current whose equation is 15 cos 100πt A. What is the rms values of the current in the load?

A. 29.15 A

B. 40 A

C. 20.6 A

D. 10 A

Solution:

432. It is a rotating sector that represent either current or voltage in an AC circuit.

A. Resistance

B. Phasor

C. polar diagram

D. velocity

Solution:

433. The relationship of the voltage across an inductor to its current is described as

A. Leading the current by 90 deg

B. Lagging the current by 90 deg

C. Leading the current by 180 deg

D. In phase with the current

Solution:

434. Find the phase angle between the voltage across through the circuit when Xc is 25 ohms, R is 100 ohms and XL is 50 ohms.

A. 76 deg with the voltage leading the current

B. 24 deg with the voltage lagging the current

C. 14 deg with the voltage leading the current

D. 76 deg with the voltage lagging the current

Solution:

435. Calculate the period of an alternating current having a equation of I=20sin 120πt

A. 4.167 ms

B. 8.33 ms

C. 16.67 ms

D. 33.33 ms

Solution:

436. What do you mean by root-mean-square (rms) value?

A. It is the average value

B. It is the effective value

C. It is the value that causes the same heating effect as the DC voltage

D. b or c

Solution:

437. The maximum instances value of a varying current, voltage or power equal to 1.414 times the effective value of a sine wave.

A. RMS value

B. Peak value

C. Effective value

D. Peak to Peak value

Solution:

438. If an AC signal has a peak voltage of 55 V, what is the average value?

A. 35 V

B. 61.05V

C. 86.34 V

D. 38.89 V

Solution:

439. If an AC signal has an average voltage of 18 V, what is the rms voltage?

A. 12.726 V

B. 19.980 V

C. 25.380 V

D. 16.213 V

Solution:

440. A 220-V, 60Hz is driving a series RL circuit. Determine the current if R = 100 ohms and 20 mH inductance

A. 2.2 A (lagging)

B. 2.0 A (lagging)

Solution:

441. Ignoring any inductive effects, what is the impedance of RC series capacitor made up of a 56K ohm resistor and a 0.33 uF capacitor at a signal frequency of 4650 Hz.

A. 66730 ohms

B. 57019 ohms

C. 45270 ohms

D. 10730 ohms

Solution:

442.What is the time constant of a 500 mH coil and a 3300 ohm resistor in series?

A. 0.00015 sec

B. 6.6 sec

C. 0.0015 sec

D. 0.0000015 sec

Solution:

443. What is the relationship between frequency and the value of XC ?

A. Frequency has no effect

B. XC varies inversely with frequency

C. XC varies indirectly with frequency

D. XC varies directly with frequency

Solution:

444. The reactance of a 25 mH coil at 5000 Hz which of the following?

A. 785 ohms

B. 785000 ohms

C. 13 ohms

D. 0.0012 ohms

Solution:

445. There are no transients in pure resistive circuits because they

A. Offer high resistance

B. Obey ohm’s Law

C. Are linear circuits

D. Have no stored energy

Solution:

446. The reciprocal of capacitance is called

A. Conductance

B. Elastance

C. Permitivity

D. permeability

Solution:

447. The AC system is preferred over DC system because

A. Ac voltages can easily changed in magnitude

B. Dc motors do not have fine speed control

C. High voltage AC transmission is less efficient

D. DC voltage cannot be used for domestic appliances

Solution:

448. An alternating voltage is given by v = 20 sin 157 t. The frequency of the alternating voltage is

A. 50 Hz

B. 25 HZ

C. 100 Hz

D. 75 Hz

Solution:

449. An alternating current given by i = 10 sin 314 t. The time taken to generate two cycles of current is

A. 20 ms

B. 10 ms

C. 40 ms

D. 50 ms

Solution:

450. In a pure resistive circuit, the instantaneous voltage and are current are given by:

v = 250sin314t i = 10sin314t

The peak power in the circuit is

A.1250 W

B. 25 W

C. 2500 W

D. 250 w

Solution:

#### Questions and Answers in Electrical Circuit

Following is the list of practice exam test questions in this brand new series:

MCQ in Electrical Circuit
PART 1: MCQ from Number 1 – 50                        Answer key: PART 1
PART 2: MCQ from Number 51 – 100                   Answer key: PART 2
PART 3: MCQ from Number 101 – 150                 Answer key: PART 3
PART 4: MCQ from Number 151 – 200                 Answer key: PART 4
PART 5: MCQ from Number 201 – 250                 Answer key: PART 5
PART 6: MCQ from Number 251 – 300                 Answer key: PART 6
PART 7: MCQ from Number 301 – 350                 Answer key: included
PART 8: MCQ from Number 351 – 400                 Answer key: included
PART 9: MCQ from Number 401 – 450                 Answer key: included
PART 10: MCQ from Number 451 – 500                 Answer key: included

### Complete List of MCQ in Electronics Engineering per topic

P inoyBIX educates thousands of reviewers and students a day in preparation for their board examinations. Also provides professionals with materials for their lectures and practice exams. Help me go forward with the same spirit.

“Will you subscribe today via YOUTUBE?”

Subscribe

PinoyBIX Engineering. © 2014-2020 All Rights Reserved | How to Donate? |  