MCQOPTIONS
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MCQOPTIONS
This section includes 104 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
If a 100 resistance is connected to a 100 capacitive reactance in a series circuit, the impedance equals 200 . |
| A. | True |
| B. | False |
| Answer» C. | |
| 2. |
If the bandwidth of an low-pass filter is 20 kHz, the cutoff frequency is also 20 kHz. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 3. |
When a series circuit is used as a low-pass filter, the output is taken from across the capacitor. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 4. |
The current lags the source voltage in a series circuit. |
| A. | True |
| B. | False |
| Answer» C. | |
| 5. |
If the frequency increases in a parallel circuit, the phase angle decreases. |
| A. | True |
| B. | False |
| Answer» C. | |
| 6. |
The output voltage from an high-pass filter increases as the frequency decreases. |
| A. | True |
| B. | False |
| Answer» C. | |
| 7. |
A 10 k capacitive reactance equals a 100 µS capacitive susceptance. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 8. |
If a series circuit contains a 120 k resistance and a 160 k capacitive reactance, the impedance equals _____. |
| A. | 280 k |
| B. | 120 k |
| C. | 160 k |
| D. | 200 k |
| Answer» E. | |
| 9. |
In a series circuit, the phase difference between the capacitor and the resistor voltages ___. |
| A. | depends on the values of |
| B. | and |
| C. | equals 0° |
| D. | equals 90° |
| E. | depends on the value of the input voltage |
| Answer» D. equals 90° | |
| 10. |
If the impedance equals 2 k in a parallel circuit, the admittance equals ___. |
| A. | More information is needed in order to find the admittance. |
| B. | 2 kS |
| C. | 4 kS |
| D. | 500 µS |
| Answer» E. | |
| 11. |
The hypotenuse of the right triangle of a vector diagram for and is _______________. |
| A. | impedance |
| B. | current |
| C. | voltage |
| D. | power |
| Answer» B. current | |
| 12. |
When the resistance is greater than the capacitive reactance in a series circuit, the phase angle is ___. |
| A. | 0° |
| B. | between 0° and 45° |
| C. | between 45° and 90° |
| D. | 45° |
| Answer» C. between 45° and 90° | |
| 13. |
Resistance is the same as impedance in an circuit. |
| A. | True |
| B. | False |
| Answer» C. | |
| 14. |
In parallel circuits, the larger the value of , the larger the phase angle. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 15. |
Which statement about a series circuit is true? |
| A. | The capacitor's voltage drop is in phase with the resistor's voltage drop. |
| B. | The current leads the source voltage. |
| C. | The current lags the source voltage. |
| D. | The resistor voltage lags the current. |
| Answer» C. The current lags the source voltage. | |
| 16. |
What is the effect of increasing the resistance in a series circuit? |
| A. | There will be no effect at all. |
| B. | The current will increase. |
| C. | The phase shift will decrease. |
| D. | The input voltage will increase. |
| Answer» D. The input voltage will increase. | |
| 17. |
What is the phase angle for a parallel circuit consisting of a 500 kHz, 5 Vac source with a 47 pF capacitor, and a 4.7 k resistor in parallel? |
| A. | 55.3° |
| B. | –55.3° |
| C. | 34.8° |
| D. | –34.8° |
| Answer» D. –34.8° | |
| 18. |
In a 20 Vac series circuit, if 20 V is read across the resistor and 40 V is measured across the capacitor, the applied voltage is |
| A. | 45 Vac |
| B. | 50 Vac |
| C. | 60 Vac |
| D. | 65 Vac |
| Answer» B. 50 Vac | |
| 19. |
If the resistor drops 6 V and the capacitor drops 8 V in a series circuit, the source voltage equals 10 V. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 20. |
In a series circuit, the phase difference between the current and the source voltage _____. |
| A. | depends on the values of |
| B. | and |
| C. | equals 0° |
| D. | equals 90° |
| E. | depends on the amplitude of the input voltage |
| Answer» B. and | |
| 21. |
A 10 k capacitive reactance equals a 100 µS capacitive susceptance. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 22. |
What is the angular difference between +j4 and –j4? |
| A. | 30° |
| B. | 90° |
| C. | 180° |
| D. | 270° |
| Answer» D. 270° | |
| 23. |
The complex number 40 55° is equivalent to |
| A. | 55 + j55 |
| B. | 40 + j40 |
| C. | 45.88 + j65.52 |
| D. | 22.94 + j32.76 |
| Answer» E. | |
| 24. |
In the complex plane, the number 14 – j5 is located in the |
| A. | first quadrant |
| B. | second quadrant |
| C. | third quadrant |
| D. | fourth quadrant |
| Answer» E. | |
| 25. |
A 12 k resistor is in series with a 0.02 F capacitor across a 1.2 kHz ac source. If the current is expressed in polar form as I = 0.30° mA, what is the source voltage expressed in polar form? |
| A. | 45.6 V |
| B. | 411.3 V |
| C. | 0.411 V |
| D. | 4.11 V |
| Answer» E. | |
| 26. |
In a lag network, the output voltage lags the input voltage in phase. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 27. |
In a parallel RC circuit, there is 100 mA through the resistive branch and 100 mA through the capacitive branch. The total rms current is |
| A. | 200 mA |
| B. | 100 mA |
| C. | 282 mA |
| D. | 141 mA |
| Answer» E. | |
| 28. |
A 120 Ω resistor is in parallel with a capacitor with a capacitive reactance of 40 Ω. Both components are across a 12 V ac source. What is the magnitude of the total impedance? |
| A. | 37.9 Ω |
| B. | 3.7 Ω |
| C. | 14,400 Ω |
| D. | 4,800 Ω |
| Answer» B. 3.7 Ω | |
| 29. |
Point +4 on the complex plane is |
| A. | 4 units above the origin on the j axis |
| B. | 4 units below the origin on the j axis |
| C. | 4 units right of the origin on the real axis |
| D. | 4 units left of the origin on the real axis |
| Answer» D. 4 units left of the origin on the real axis | |
| 30. |
Positive numbers can be represented by points to the right of the origin on the horizontal axis of a graph. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 31. |
What is the value of the hypotenuse of a right triangle whose sides are 12 and 18? |
| A. | 4.24 |
| B. | 3.46 |
| C. | 2.16 |
| D. | 21.63 |
| Answer» E. | |
| 32. |
A filter passes all frequencies. |
| A. | True |
| B. | False |
| Answer» C. | |
| 33. |
When the frequency of the voltage applied to a series RC circuit is increased, the phase angle |
| A. | Increases |
| B. | Decreases |
| C. | Remains the same |
| D. | Becomes erratic |
| Answer» C. Remains the same | |
| 34. |
The resistor voltage is always out of phase with the current. |
| A. | True |
| B. | False |
| Answer» C. | |
| 35. |
A complex number represents a phasor quantity. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 36. |
A 6 kHz sinusoidal voltage is applied to a series RC circuit. The frequency of the voltage across the resistor is |
| A. | 0 Hz |
| B. | 12 kHz |
| C. | 6 kHz |
| D. | 18 kHz |
| Answer» D. 18 kHz | |
| 37. |
A 470 Ω resistor and a 0.2 µF capacitor are in parallel across a 2.5 kHz ac source. The admittance, Y, in rectangular form, is |
| A. | 212 Ω |
| B. | 2.12 mS + j3.14 mS |
| C. | 3.14 mS + j2.12 mS |
| D. | 318.3 Ω |
| Answer» C. 3.14 mS + j2.12 mS | |
| 38. |
For a certain load, the true power is 150 W and the reactive power is 125 VAR. The apparent power is |
| A. | 19.52 W |
| B. | 195.2 W |
| C. | 275 W |
| D. | 25 W |
| Answer» C. 275 W | |
| 39. |
An imaginary number is one that exists only in the mind of the mathematician. |
| A. | True |
| B. | False |
| Answer» C. | |
| 40. |
A 12 kΩ resistor is in series with a 0.02 µF capacitor across a 1.2 kHz ac source. If the current is expressed in polar form as I = 0.3 ∠0° mA, what is the source voltage expressed in polar form? |
| A. | 45.6 V |
| B. | 411.3 V |
| C. | 0.411 V |
| D. | 4.11 V |
| Answer» E. | |
| 41. |
A capacitor with 150 Ω of capacitive reactance is across an ac source. The impedance, expressed in polar form, is |
| A. | Z = 150 |
| B. | Z = 150 ∠90°O |
| C. | Z = 150 ∠-90°O |
| D. | Z = 150 ∠180°O |
| Answer» D. Z = 150 ∠180°O | |
| 42. |
The circuit phase angle is the angle between the total current and the applied (source) voltage. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 43. |
Complex numbers can be added and subtracted but not multiplied or divided. |
| A. | True |
| B. | False |
| Answer» C. | |
| 44. |
The polar form of a complex number consists of a real part and a j part. |
| A. | True |
| B. | False |
| Answer» C. | |
| 45. |
In the complex plane, the number 14 - j5 is located in the |
| A. | First quadrant |
| B. | Second quadrant |
| C. | Third quadrant |
| D. | Fourth quadrant |
| Answer» E. | |
| 46. |
In the complex plane, the number 4 + j3 is located in the |
| A. | First quadrant |
| B. | Second quadrant |
| C. | Third quadrant |
| D. | Fourth quadrant |
| Answer» B. Second quadrant | |
| 47. |
A 47 Ω resistor and a capacitor with a capacitive reactance of 120 Ω are in series across an ac source. What is the circuit impedance, Z? |
| A. | 129 Ω |
| B. | 12.9 Ω |
| C. | 167 Ω |
| D. | 73 Ω |
| Answer» B. 12.9 Ω | |
| 48. |
A 47 Ω resistor and a capacitor with 150 Ω of capacitive reactance are in series across an ac source. The impedance, expressed in rectangular form, is |
| A. | Z = 47 Ω + j150 Ω |
| B. | Z = 47 Ω - j150 Ω |
| C. | Z = 197 Ω |
| D. | Z = 103 Ω |
| Answer» C. Z = 197 Ω | |
| 49. |
The power factor (PF) indicates how much of the apparent power is true power. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 50. |
A resistor and a capacitor are in series across a 20 V ac source. Circuit impedance is 4.33 kΩ. Current flow in the circuit is |
| A. | 9.2 mA |
| B. | 92 mA |
| C. | 4.6 mA |
| D. | 460 mA |
| Answer» D. 460 mA | |