MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 159 Mcqs, each offering curated multiple-choice questions to sharpen your BITSAT knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Observe the given figure. If the diode is an ideal diode, then what are the values of ID and VD respectively? |
| A. | 10 A, 2 V |
| B. | 2 A, 10 V |
| C. | 0 A, 0.2 V |
| D. | 0.2 A, 0 V |
| Answer» E. | |
| 2. |
In a fullwave rectifier circuit with centre tap transformer, if voltage between one end of secondary winding and centre tap is 300 V peak, then PIV (peak inverse voltage) is |
| A. | 300 V |
| B. | 150 V |
| C. | 600 V |
| D. | 900 V |
| Answer» D. 900 V | |
| 3. |
In figure shown below, the Peak Inverse Voltage (PIV) required for diode is |
| A. | 300 V |
| B. | 200 V |
| C. | 100 V |
| D. | 400 V |
| Answer» E. | |
| 4. |
Match the columns.1. a. Schottky diode2. b. Junction diode3. c. Tunnel diode4. d. Varactor diode |
| A. | 1 - c, 2 - a, 3 - b, 4 - d |
| B. | 1 - c, 2 - b, 3 - a, 4 - d |
| C. | 1 - b, 2 - c, 3 - a, 4 - d |
| D. | 1 - b, 2 - c, 3 - d, 4 - a |
| Answer» D. 1 - b, 2 - c, 3 - d, 4 - a | |
| 5. |
In a Schottky diode, current flows because of ________. |
| A. | Majority Carriers only |
| B. | Minority Carriers only |
| C. | Holes only |
| D. | Electrons only |
| Answer» B. Minority Carriers only | |
| 6. |
In the full-wave rectifier, relation between peak value and rms value is: |
| A. | \(V_p=\sqrt{4} V_{rms}\) |
| B. | \(V_p=\sqrt{3} V_{rms}\) |
| C. | \(V_p=\sqrt{2} V_{rms}\) |
| D. | \(V_p=\sqrt{1.2} V_{rms}\) |
| Answer» D. \(V_p=\sqrt{1.2} V_{rms}\) | |
| 7. |
A diode will work satisfactorily in: |
| A. | First and third quadrant only |
| B. | First and fourth quadrant only |
| C. | Third quadrant only |
| D. | First quadrant only |
| Answer» E. | |
| 8. |
Assuming Zener diode D1 has current-voltage characteristics as shown below on the right and forward voltage drop of diode D2 is 0.7 V, the voltage V0 in the circuit shown below is |
| A. | 3.7 V |
| B. | 2.7 V |
| C. | 2.2 V |
| D. | 0 V |
| Answer» D. 0 V | |
| 9. |
A half-wave rectifier is used to supply 50 V d.c. to a resistive load of 800 Ω. The diode has resistance of 25 Ω. What is the required a.c. voltage? |
| A. | 50 π |
| B. | 51.5 π |
| C. | 25.7 π |
| D. | 25 π |
| Answer» C. 25.7 π | |
| 10. |
A semiconductor diode used as a rectifier must be operated |
| A. | in the non-linear region |
| B. | in the linear region |
| C. | in the cut-off region |
| D. | none of these |
| Answer» B. in the linear region | |
| 11. |
Assuming that diode in the given circuit is ideal, the voltage Vo is |
| A. | 2 V |
| B. | 3 V |
| C. | 3.5 V |
| D. | 1 V |
| Answer» B. 3 V | |
| 12. |
If the circuit shown has to function as a clamping circuit, which one of the following conditions should be satisfied for sinusoidal signal of period T? |
| A. | RC ≪ T |
| B. | RC = 0.35T |
| C. | RC ≈ T |
| D. | RC T |
| Answer» E. | |
| 13. |
In a clipper circuit, dc source is set to zero voltage, then the circuit acts like a: |
| A. | Chopper |
| B. | Clamper |
| C. | Demodulator |
| D. | Rectifier |
| Answer» E. | |
| 14. |
A full-wave diode rectifier is applied with a voltage from a 60 V – 0 – 60 V transformer. Load and diode forward resistance are 100 Ω and 10 Ω respectively. The average output voltage of the rectifier circuit is: |
| A. | 34.7 V |
| B. | 24.6 V |
| C. | 17.4 V |
| D. | 49.1 V |
| Answer» B. 24.6 V | |
| 15. |
Calculate the temperature coefficient in %/° C of an 8.6-V nominal Zener diode at 30° C if the nominal voltage is 9.4 V at 100° C. |
| A. | 0.1251 |
| B. | 0.1142 |
| C. | 0.1328 |
| D. | 0.1221 |
| Answer» D. 0.1221 | |
| 16. |
A silicon diode is operating at 25°C with a forward bias of 0.6 V and a current of 0.5 A. If the current is held constant at 0.5 A and the temperature of the device is raised to 75° C, the voltage across the diode is likely to be |
| A. | 0.49 V |
| B. | 0.60 V |
| C. | 0.66 V |
| D. | 0.75 V |
| Answer» B. 0.60 V | |
| 17. |
If a diode shows equal resistance but not zero in both directions then the diode must be ____. |
| A. | short |
| B. | defective |
| C. | working fine |
| D. | open |
| Answer» C. working fine | |
| 18. |
For smooth and reliable operation of an amplifier using BJT, it is necessary that the circuit must be properly designed from the point of view of bias stabilization, because:1. Reverse saturation current ICO increases with rise in temperature.2. VBE decreases with rise in temperature.3. hFE or β changes with change of temperature and replacement of the transistor.4. hFE or β changes with change in collector supply voltage. |
| A. | 1, 2 and 3 only |
| B. | 1, 2 and 4 only |
| C. | 2, 3 and 4 only |
| D. | 1, 2, 3 and 4 |
| Answer» B. 1, 2 and 4 only | |
| 19. |
Consider the following statements:A power supply uses bridge rectifier with a capacitor input filter. If one of the diodes is defective, then1. The dc load voltage will be lower than its expected value2. Ripple frequency will be lower than its expected value3. The surge current will increase considerablyWhich of the above statements are correct? |
| A. | 1 and 2 only |
| B. | 1 and 3 only |
| C. | 2 and 3 only |
| D. | 1, 2 and 3 |
| Answer» E. | |
| 20. |
One of the following is a negative resistance device |
| A. | P-N junction diode |
| B. | Field effect transistor |
| C. | Silicon controlled rectifier |
| D. | Bipolar transistor |
| Answer» D. Bipolar transistor | |
| 21. |
An ideal voltage regulator has a voltage regulation of: |
| A. | 50 |
| B. | 100 |
| C. | 0 |
| D. | 5 |
| Answer» D. 5 | |
| 22. |
In an arc rectifier, the drop in voltage at the cathode is approximately |
| A. | 1 volt |
| B. | 6 to 7 volts |
| C. | 60 to 70 volts |
| D. | 1.2 to 7 volts |
| Answer» C. 60 to 70 volts | |
| 23. |
In the figure, D1 is a real silicon p-n junction diode with a drop of 0.7 V under forward bias condition and D2 is a Zener diode with breakdown voltage of -6.8 V. The input Vin(t) is a periodic square wave of period T, whose one period is shown in the figure.Assuming 10τ ≪ T, where τ is the time constant of the circuit, the maximum and minimum values of the output waveform are respectively, |
| A. | 7.5 V and -20.5 V |
| B. | 6.1 V and -21.9 V |
| C. | 7.5 V and -21.2 V |
| D. | 6.1 V and -22.6 V |
| Answer» B. 6.1 V and -21.9 V | |
| 24. |
Determine the rectification efficiency of a diode having an internal resistance of 20 Ω and 1000 ohm load from a 110 V rms source of supply. |
| A. | 40% |
| B. | 22% |
| C. | 15% |
| D. | 100% |
| Answer» B. 22% | |
| 25. |
A half-wave rectifier operates from a 50 Hz supply and provides a peak output voltage of 60 V across 600 Ω resistance. If one limits the peak ripple voltage across the load as 15 V then the value of the capacitor filter will be: |
| A. | 11.7 μF |
| B. | 87.5 μF |
| C. | 58.5 μF |
| D. | 23.4 μF |
| Answer» E. | |
| 26. |
A half-wave rectifier built using a diode is connected to a sinusoidal voltage of 120 V (rms) at a frequency of 50 Hz. The load resistance is 5 Ω. The power absorbed by the resistor is: |
| A. | 1220 W |
| B. | 610 W |
| C. | 720 W |
| D. | 1440 W |
| Answer» E. | |
| 27. |
An example of solid-state device is: |
| A. | Zener diode |
| B. | Triode |
| C. | Pentode |
| D. | Thyratron |
| Answer» B. Triode | |
| 28. |
A single-phase full-wave rectifier uses semiconductor diodes. The transformer voltage is 35 V rms to the center tap. The load consists of a 40 μF capacitor in parallel with a 250 Ω resistor. The diode and transformer resistances and leakage reactance are neglected. If the power line frequency is 50 Hz, the DC in the circuit will be |
| A. | 132 mA |
| B. | 144 mA |
| C. | 156 mA |
| D. | 168 mA |
| Answer» B. 144 mA | |
| 29. |
A potential of 7 V is applied to a silicon diode in series with a resistance of 1 kΩ. The current through the diode is |
| A. | 7 mA |
| B. | 6.3 mA |
| C. | 0.7 mA |
| D. | 0 |
| Answer» C. 0.7 mA | |
| 30. |
Find the peak-to-peak ripple voltage of half-wave rectifier and filter circuit which has a 680 μF filter capacitor, an average output voltage of 30 V, and a 220Ω load resistance. The mains frequency is 50 Hz. |
| A. | 3.51 V |
| B. | 4.01 V |
| C. | 3.83 V |
| D. | 2.84 V |
| Answer» C. 3.83 V | |
| 31. |
Among these alternatives, the PIV rating of which diode is lower than that of equivalent vacuum diode? |
| A. | PN junction Diode |
| B. | Crystal diode |
| C. | Tunnel diode |
| D. | Small single diode |
| Answer» C. Tunnel diode | |
| 32. |
In a tunnel diode, the width of the junction barrier is |
| A. | Directly proportional as the square root of impurity concentration |
| B. | Inversely proportional as the square root of impurity concentration |
| C. | Directly proportional as square of impurity concentration |
| D. | Inversely proportional as square of impurity concentration |
| Answer» C. Directly proportional as square of impurity concentration | |
| 33. |
Crest factor is defined as: |
| A. | Peak value / Avg. value |
| B. | RMS value / Peak value |
| C. | Avg. value / Peak value |
| D. | Peak value / RMS value |
| Answer» E. | |
| 34. |
A voltage source VAB = 4 sin wt is applied to the terminals A and B of the circuit shown in the given figure. The diodes are assumed to be ideal. The impedance by the circuit across the terminals A and B is |
| A. | 5 k |
| B. | 10 k |
| C. | 15 k |
| D. | 20 k |
| Answer» C. 15 k | |
| 35. |
A diode with VF = 0.7 V is connected as a half-wave rectifier. The load resistance is 500 Ω and the RMS AC input is 22 V.Find the peak output voltage. |
| A. | 32.2 V |
| B. | 34.1 V |
| C. | 30.4 V |
| D. | 22.0 V |
| Answer» D. 22.0 V | |
| 36. |
In a feedback series regulator circuit, the output voltage is regulated by controlling the |
| A. | Magnitude of the I/P voltage |
| B. | Gain of the feedback transistor |
| C. | Voltage drop across the series pass transistor |
| D. | Reference voltage |
| Answer» E. | |
| 37. |
A forward potential of 8 V is applied to a Ge diode. A resistance of 1 KΩ is in series with the diode. The current through the diode is ______ |
| A. | 10 mA |
| B. | 7.3 mA |
| C. | 7.7 mA |
| D. | 0 mA |
| Answer» D. 0 mA | |
| 38. |
A rectifier (without filter) with fundamental ripple frequency equal to twice the mains frequency, has ripple factor of 0.482 and power conversion efficiency equal to 81.2%. The rectifier is:i. Bridge rectifierii. Full-wave (non bridge) rectifieriii. Half-wave rectifier.Which of these are correct? |
| A. | ii and iii only |
| B. | ii only |
| C. | i and ii only |
| D. | i, ii and iii |
| Answer» D. i, ii and iii | |
| 39. |
In case of Bridge wave rectifier the ripple factor is |
| A. | 1.21 |
| B. | 0.5 |
| C. | 0.48 |
| D. | 1 |
| Answer» D. 1 | |
| 40. |
For a lower Q-point of operation, the dynamic resistance of a diode is |
| A. | lower |
| B. | higher |
| C. | varies |
| D. | no change |
| Answer» C. varies | |
| 41. |
A PN junction in series with a 100 ohm resistor is forward biased so that a current of 100 mA flows. If voltage across the combination is instantaneously reversed to 10 V at time t = 0, the reverse current that flows through the junction at t = 0 is approximately given by. |
| A. | 0 mA |
| B. | 200 mA |
| C. | 50 mA |
| D. | 100 mA |
| Answer» E. | |
| 42. |
For a full wave rectifier, with sinusoidal input and inductor as filter, ripple factor for maximum load current and minimum load current conditions are respectively |
| A. | 0.1 and 1 |
| B. | 0.1 and 0.47 |
| C. | 0 and 0.47 |
| D. | 0 and 0.22 |
| Answer» D. 0 and 0.22 | |
| 43. |
At a constant collector current, the magnitude of base-emitter voltage decreases by 2 mV for every XX rise in temperature. Here XX is _________ |
| A. | 3° C |
| B. | 9° C |
| C. | 4° C |
| D. | 1° C |
| Answer» E. | |
| 44. |
Arsenic mixes with ______ to form a N-type semiconductor: |
| A. | Phosphorus |
| B. | Germanium |
| C. | Aluminum |
| D. | Gallium |
| Answer» C. Aluminum | |
| 45. |
How many diodes are used to construct half wave, full wave and bridge rectifier circuits, respectively? |
| A. | 2, 1, 4 |
| B. | 2, 4, 1 |
| C. | 4, 1, 2 |
| D. | 1, 2, 4 |
| Answer» E. | |
| 46. |
A silicon diode has a forward voltage drop of 1.2 V for a forward DC current of 100 mA. It has a reverse current of 1 μA for a reverse voltage of 10 V. calculate the AC resistance at a forward DC current of 2.5 mA. |
| A. | 15 Ω |
| B. | 12 Ω |
| C. | 20 Ω |
| D. | 10 Ω |
| Answer» B. 12 Ω | |
| 47. |
Find the output voltage of the given network if Ein = 6 V and the Zener breakdown voltage of the Zener diode is 10 V. |
| A. | 4 V |
| B. | 0 V |
| C. | 10 V |
| D. | 6 V |
| Answer» C. 10 V | |
| 48. |
IC LM7815 is a |
| A. | Voltage Regulator with a +5 V output voltage |
| B. | Voltage Regulator with a -5 V output voltage |
| C. | Voltage Regulator with a +15 V output voltage |
| D. | Voltage Regulator with a -15 V output voltage |
| Answer» D. Voltage Regulator with a -15 V output voltage | |
| 49. |
A diode with no junction that is widely used with a cavity resonator to form a microwave oscillator is a / an: |
| A. | IMPATT diode |
| B. | TRAPATT diode |
| C. | TUNNEL diode |
| D. | GUNN diode |
| Answer» E. | |
| 50. |
A 10 V reference source is designed from a 30 V supply using a Zener diode and a resistance. The test current of the Zener diode is 20 mA. If the supply voltage drops to 20 V, the Zener current will be: |
| A. | 5 mA |
| B. | 15 mA |
| C. | 20 mA |
| D. | 10 mA |
| Answer» E. | |