MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 214 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering Questions knowledge and support exam preparation. Choose a topic below to get started.
| 101. |
The safest value of current the human body can carry for more than 3 second is_________? |
| A. | 4 mA |
| B. | 9 mA |
| C. | 15 mA |
| D. | 25 mA |
| Answer» C. 15 mA | |
| 102. |
In a series L-C circuit at the resonant frequency the__________? |
| A. | current is maximum |
| B. | current is minimum |
| C. | impedance is maximum |
| D. | voltage across C is minimum |
| Answer» B. current is minimum | |
| 103. |
Time constant of a capacitive circuit__________? |
| A. | increases with the decrease of capacitance and decrease of resistance |
| B. | increases with the decrease of capacitance and increase of resistance |
| C. | increases with the increase of capacitance and decrease of resistance |
| D. | increase with increase of capacitance and increase of resistance |
| Answer» E. | |
| 104. |
In any A.C. circuit always__________? |
| A. | apparent power is more than actual power |
| B. | reactive power is more than apparent power |
| C. | actual power is more than reactive power |
| D. | reactive power is more than actual power |
| Answer» B. reactive power is more than apparent power | |
| 105. |
Which of the following coil will have large resonant frequency __________? |
| A. | A coil with large resistance |
| B. | A coil with low resistance |
| C. | A coil with large distributed capacitance |
| D. | A coil with low distributed capacitance |
| Answer» D. A coil with low distributed capacitance | |
| 106. |
In a purely inductive circuit__________? |
| A. | actual power is zero |
| B. | reactive power is zero |
| C. | apparent power is zero |
| D. | none of above is zero |
| Answer» B. reactive power is zero | |
| 107. |
In a R-L-C circuit_________? |
| A. | power is consumed in resistance and is equal to I R |
| B. | exchange of power takes place between inductor and supply line |
| C. | exchange of power takes place between capacitor and supply line |
| D. | exchange of power does not take place between resistance and the supply line |
| E. | all above are correct |
| Answer» F. | |
| 108. |
Power factor of electric bulb is__________? |
| A. | zero |
| B. | lagging |
| C. | leading |
| D. | unity |
| Answer» E. | |
| 109. |
Which of the following statements pertains to resistors only _____________? |
| A. | can dissipate considerable amount of power |
| B. | can act as energy storage devices |
| C. | connecting them in parallel in¬creases the total value |
| D. | oppose sudden changes in voltage |
| Answer» B. can act as energy storage devices | |
| 110. |
Which of the following waves has the highest value of peak factor ___________? |
| A. | Square wave |
| B. | Sine wave |
| C. | Half wave rectified sine wave |
| D. | Triangular wave |
| Answer» D. Triangular wave | |
| 111. |
Wire-wound resistors are unsuitable for use at high frequencies because they_______? |
| A. | create more electrical noise |
| B. | are likely to melt under excessive eddy current heat |
| C. | consume more power |
| D. | exhibit unwanted inductive and capacitive effects |
| Answer» E. | |
| 112. |
Which of the following refers to a parallel circuit ? |
| A. | The current through each element is same |
| B. | The voltage across element is in proportion to it’s resistance value |
| C. | The equivalent resistance is greater than any one of the resistors |
| D. | The current through any one element is less than the source current |
| Answer» E. | |
| 113. |
Which of the following coil will have large resonant frequency __________? |
| A. | A coil with large resistance |
| B. | A coil with low resistance |
| C. | A coil with large distributed capacitance |
| D. | A coil with low distributed capacitance |
| Answer» D. A coil with low distributed capacitance | |
| 114. |
When an alternating current passes through an ohmic resistance the electrical power converted into heat is__________? |
| A. | apparent power |
| B. | true power |
| C. | reactive power |
| D. | none of the above |
| Answer» C. reactive power | |
| 115. |
What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value________ ? |
| A. | 0° |
| B. | 45° |
| C. | 90° |
| D. | 180° |
| Answer» D. 180° | |
| 116. |
Two waves of the same frequency have opposite phase when the phase angle between them is_________? |
| A. | 360° |
| B. | 180° |
| C. | 90° |
| D. | 0° |
| Answer» C. 90° | |
| 117. |
Time constant of an inductive circuit_________? |
| A. | increases with increase of inductance and decrease of resistance |
| B. | increases with the increase of inductance and the increase of resistance |
| C. | increases with the decrease of inductance and decrease of resistance |
| D. | increases with decrease of inductance and increase of resistance |
| Answer» B. increases with the increase of inductance and the increase of resistance | |
| 118. |
Time constant of a capacitive circuit__________? |
| A. | increases with the decrease of capacitance and decrease of resistance |
| B. | increases with the decrease of capacitance and increase of resistance |
| C. | increases with the increase of capacitance and decrease of resistance |
| D. | increase with increase of capacitance and increase of resistance |
| Answer» E. | |
| 119. |
Time constant of an inductive circuit___________? |
| A. | increases with increase of inductance and decrease of resistance |
| B. | increases with the increase of inductance and the increase of resistance |
| C. | increases with decrease of inductance and decrease of resistance |
| D. | increases with decrease of inductance and increase of resistance |
| Answer» B. increases with the increase of inductance and the increase of resistance | |
| 120. |
Time constant of a circuit is the time in seconds taken after the application of voltage to each___________? |
| A. | 25% of maximum value |
| B. | 50% of maximum value |
| C. | 63% of maximum value |
| D. | 90% of the maximum value |
| Answer» D. 90% of the maximum value | |
| 121. |
The voltage of domestic supply is 220V. This figure represents__________? |
| A. | mean value |
| B. | r.m.s. value |
| C. | peak value |
| D. | average value |
| Answer» B. r.m.s. value | |
| 122. |
The transient currents are associated with the____________? |
| A. | changes in the stored energy in the inductors and capacitors |
| B. | impedance of the circuit |
| C. | applied voltage to the circuit |
| D. | resistance of the circuit |
| Answer» B. impedance of the circuit | |
| 123. |
The time constant of the capacitance circuit is defined as the time during which voltage________? |
| A. | falls to 36.8% of its final steady value |
| B. | rises to 38.6% of its final steady value |
| C. | rises to 63.2% of its final steady value |
| D. | none of the above |
| Answer» D. none of the above | |
| 124. |
The time constant of a series R-C circuit is given by____________? |
| A. | R/C |
| B. | RC2 |
| C. | RC |
| D. | R2C |
| Answer» D. R2C | |
| 125. |
The square waveform of current has following relation between r.m.s. value and average value? |
| A. | r.m.s. value is equal to average value |
| B. | r.m.s. value of current is greater than average value |
| C. | r.m.s. value of current is less than average value |
| D. | none of the above |
| Answer» B. r.m.s. value of current is greater than average value | |
| 126. |
The series and parallel resonance on L-C circuit’ differs in that_________? |
| A. | series resistance needs a low-resistance source for sharp rise in current |
| B. | series resonance needs a high-resistance source for sharp increase in current |
| C. | parallel resonance needs a low-resistance source for a sharp in¬crease in impedance |
| D. | parallel resonance needs a low-resistance source for a sharp rise in line current |
| Answer» B. series resonance needs a high-resistance source for sharp increase in current | |
| 127. |
The safest value of current the human body can carry for more than 3 second is_________? |
| A. | 4 mA |
| B. | 9 mA |
| C. | 15 mA |
| D. | 25 mA |
| Answer» C. 15 mA | |
| 128. |
The r.m.s. value of pure cosine function is_________? |
| A. | 0.5 of peak value |
| B. | 0.707 of peak value |
| C. | same as peak value |
| D. | zero |
| Answer» C. same as peak value | |
| 129. |
The r.m.s. value of half wave rectified sine wave is 200 V. The r.m.s. value of full wave rectified AC. will be___________? |
| A. | 282.8 V |
| B. | 141.4 V |
| C. | 111 V |
| D. | 100 V |
| Answer» B. 141.4 V | |
| 130. |
The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces__________? |
| A. | the more heat than produced by A.C. when flowing through the same circuit |
| B. | the same heat as produced by A.C. when flowing through the same circuit |
| C. | the less heat than produced by A.C. flowing through the same circuit |
| D. | none of the above |
| Answer» C. the less heat than produced by A.C. flowing through the same circuit | |
| 131. |
The r.m.s. value and mean value is the same in the case of___________? |
| A. | triangular wave |
| B. | sine wave |
| C. | square wave |
| D. | half wave rectified sine wave |
| Answer» D. half wave rectified sine wave | |
| 132. |
The r.m.s. value of a sinusoidal A.C. current is equal to its value at an angle of_______degrees? |
| A. | 90 |
| B. | 60 |
| C. | 45 |
| D. | 30 |
| Answer» D. 30 | |
| 133. |
The reactance offered by a capacitor to alternating current of frequency 50 Hz is 20 Q. If frequency is increased to 100 Hz, reactance becomes_______ohms? |
| A. | 2.5 |
| B. | 5 |
| C. | 10 |
| D. | 15 |
| Answer» D. 15 | |
| 134. |
The ratio of active power to apparent power is known as factor__________? |
| A. | demand |
| B. | load |
| C. | power |
| D. | form |
| Answer» D. form | |
| 135. |
The purpose of a parallel circuit resonance is to magnify________? |
| A. | current |
| B. | voltage |
| C. | power |
| D. | frequency |
| Answer» C. power | |
| 136. |
The power is measured in terms of decibles in case of_________? |
| A. | electronic equipment |
| B. | transformers |
| C. | current transformers |
| D. | auto transformers |
| Answer» B. transformers | |
| 137. |
The power factor of a D.C. circuit is always__________? |
| A. | less than unity |
| B. | unity |
| C. | greater than unity |
| D. | zero |
| Answer» C. greater than unity | |
| 138. |
The power factor at resonance in R-L- C parallel circuit is________? |
| A. | zero |
| B. | 0.08 lagging |
| C. | 0.8 leading |
| D. | unity |
| Answer» E. | |
| 139. |
The power consumed in a circuit element will be least when the phase difference between the current and voltage is__________? |
| A. | 180″ |
| B. | 90° |
| C. | 60° |
| D. | 0° |
| Answer» C. 60° | |
| 140. |
The power consumed in a circuit element will be least when the phase difference between the current and voltage is________? |
| A. | 180″ |
| B. | 90° |
| C. | 60° |
| D. | 0° |
| Answer» C. 60° | |
| 141. |
The phosphors for which of the following pair are 180° out of phase for VL, VC and VR______? |
| A. | Vc and VR |
| B. | VL and VR |
| C. | Vc and VL |
| D. | none of the above |
| Answer» D. none of the above | |
| 142. |
The period of a wave is___________? |
| A. | the same as frequency |
| B. | time required to complete one cycle |
| C. | expressed in amperes |
| D. | none of the above |
| Answer» C. expressed in amperes | |
| 143. |
The period of a sine wave is _____ seconds. Its frequency is |
| A. | 20 Hz |
| B. | 30 Hz |
| C. | 40 Hz |
| D. | 50 Hz |
| Answer» E. | |
| 144. |
The peak value of a sine wave is 200 V. Its average value is___________? |
| A. | 127.4 V |
| B. | 141.4 V |
| C. | 282.8 V |
| D. | 200V |
| Answer» C. 282.8 V | |
| 145. |
The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is__________? |
| A. | 12 kW |
| B. | 22 kW |
| C. | 32 kW |
| D. | 64 kW |
| Answer» D. 64 kW | |
| 146. |
The inductance of a coil can be increased by_________? |
| A. | increasing core length |
| B. | decreasing the number of turns |
| C. | decreasing the diameter of the former |
| D. | choosing core material having high relative permeability |
| Answer» E. | |
| 147. |
The frequency of an alternating current is____________? |
| A. | the speed with which the alternator runs |
| B. | the number of cycles generated in one minute |
| C. | the number of waves passing through a point in one second |
| D. | the number of electrons passing through a point in one second |
| Answer» D. the number of electrons passing through a point in one second | |
| 148. |
The frequency of domestic power supply in Pakistan is_________? |
| A. | 200 Hz |
| B. | 100 Hz |
| C. | 60 Hz |
| D. | 50 Hz |
| Answer» E. | |
| 149. |
The form factor is the ratio of_______? |
| A. | peak value to r.m.s. value |
| B. | r.m.s. value to average value |
| C. | average value to r.m.s. value |
| D. | none of the above |
| Answer» C. average value to r.m.s. value | |
| 150. |
The equation of 50 Hz current sine wave having r.m.s. value of 60 A is____________? |
| A. | 60 sin 25 t |
| B. | 60 sin 50 t |
| C. | 84.84 sin 3141 |
| D. | 42.42 sin 314 t |
| Answer» D. 42.42 sin 314 t | |