MCQOPTIONS
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MCQOPTIONS
This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The flow of electrons in dielectric is due to _________ |
| A. | Conduction |
| B. | Potential difference |
| C. | Breakdown |
| D. | Resistance |
| Answer» D. Resistance | |
| 2. |
If a parallel plate capacitor of plate area 2m² and plate separation 1m store the charge of 1.77*10¯¹¹ C. What is the voltage across the capacitor? |
| A. | 1V |
| B. | 2V |
| C. | 3V |
| D. | 4V |
| Answer» B. 2V | |
| 3. |
If the charge in a capacitor is 4C and the energy stored in it is 4J, find the value of capacitance. |
| A. | 2F |
| B. | 4F |
| C. | 8F |
| D. | 16F |
| Answer» B. 4F | |
| 4. |
Which of the following expressions is correct with respect to the voltage across capacitors in series? |
| A. | V1/V2=C2/C1 |
| B. | V2/V1=C2/C1 |
| C. | V1*V2=C1*C2 |
| D. | V1/C1=V2/C2 |
| Answer» B. V2/V1=C2/C1 | |
| 5. |
For very low frequencies, capacitor acts as ________ |
| A. | Open circuit |
| B. | Short circuit |
| C. | Amplifier |
| D. | Rectifier |
| Answer» B. Short circuit | |
| 6. |
A capacitor consists of_________ |
| A. | Two conductors |
| B. | Two semiconductors |
| C. | Two dielectrics |
| D. | Two insulators |
| Answer» B. Two semiconductors | |
| 7. |
For high frequencies, capacitor acts as _________ |
| A. | Open circuit |
| B. | Short circuit |
| C. | Amplifier |
| D. | Rectifier |
| Answer» C. Amplifier | |
| 8. |
What is the voltage across a capacitor at the time of switching, that is, when t=0? |
| A. | Infinity |
| B. | 0V |
| C. | Cannot be determined |
| D. | 1V |
| Answer» C. Cannot be determined | |
| 9. |
If a 2F capacitor has 1C charge, calculate the voltage across its terminals. |
| A. | 0.5V |
| B. | 2V |
| C. | 1.5V |
| D. | 1V |
| Answer» B. 2V | |
| 10. |
Which among the following expressions relate charge, voltage and capacitance of a capacitor? |
| A. | Q=C/V |
| B. | Q=V/C |
| C. | Q=CV |
| D. | C=Q²V |
| Answer» D. C=Q²V | |
| 11. |
Calculate the time constant of a series RC circuit consisting of a 100microF capacitor in series with a 100ohm resistor. |
| A. | 0.1 sec |
| B. | 0.1 msec |
| C. | 0.01 sec |
| D. | 0.01 msec |
| Answer» D. 0.01 msec | |
| 12. |
Capacitors charge and discharge in __________ manner. |
| A. | Linear |
| B. | Constant |
| C. | Square |
| D. | Exponential |
| Answer» E. | |
| 13. |
A power factor of a circuit can be improved by placing which, among the following, in a circuit? |
| A. | Inductor |
| B. | Capacitor |
| C. | Resistor |
| D. | Switch |
| Answer» C. Resistor | |
| 14. |
When the supply frequency increases, what happens to the capacitive reactance in the circuit? |
| A. | Increases |
| B. | Decreases |
| C. | Remains the same |
| D. | Becomes zero |
| Answer» C. Remains the same | |
| 15. |
N capacitors having capacitance C are connected in series, calculate the equivalent capacitance. |
| A. | C/N |
| B. | C |
| C. | CN |
| D. | N/C |
| Answer» E. | |
| 16. |
Electric field terminates at ________ |
| A. | Positive charge |
| B. | Negative charge |
| C. | Neither positive nor negative |
| D. | Both positive and negative |
| Answer» C. Neither positive nor negative | |
| 17. |
When the potential gradient increases, what happens to the force between the plates? |
| A. | Increases |
| B. | Decreases |
| C. | Remains the same |
| D. | becomes zero |
| Answer» B. Decreases | |
| 18. |
Find the number of plates in the multi plate capacitor having C=20F absolute permittivity=5F/m, A=4m² and d=2m. |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» D. 4 | |
| 19. |
Energy stored in 2000mF capacitor charged to a potential difference of 10V is? |
| A. | 100J |
| B. | 200J |
| C. | 300J |
| D. | 400J |
| Answer» B. 200J | |
| 20. |
If the potential difference in a material is 4MV and the thickness of the material is 2m, calculate the dielectric strength. |
| A. | 2MV/m |
| B. | 4MV/m |
| C. | 6MV/m |
| D. | 8MV/m |
| Answer» B. 4MV/m | |
| 21. |
Under normal conditions capacitors have _______ |
| A. | Displacement current |
| B. | Conduction current |
| C. | Both conduction and displacement current |
| D. | Neither conduction nor displacement current |
| Answer» B. Conduction current | |
| 22. |
If the dielectric strength of a material is 4MV/m and its potential difference is 28MV, calculate the thickness of the material. |
| A. | 4m |
| B. | 7m |
| C. | 5m |
| D. | 11m |
| Answer» C. 5m | |
| 23. |
A capacitor using chemical reactions to store charge is _______ |
| A. | Paper capacitor |
| B. | Ceramic capacitor |
| C. | Polyester capacitor |
| D. | Electrolyte capacitor |
| Answer» E. | |
| 24. |
The flow of electrons which does not pass through the battery is known as ____________ |
| A. | Conduction current |
| B. | Leakage current |
| C. | Charging current |
| D. | Displacement current |
| Answer» B. Leakage current | |
| 25. |
The current in conductors connecting the voltage source to the plates of a capacitor is ______ |
| A. | Conduction current |
| B. | Leakage current |
| C. | Charging current |
| D. | Zero |
| Answer» D. Zero | |
| 26. |
The electric field strength is 10N/C and the thickness of the dielectric is 3m. Calculate the potential drop in the dielectric. |
| A. | 10V |
| B. | 20V |
| C. | 30V |
| D. | 40V |
| Answer» D. 40V | |
| 27. |
A circuit has a resistance of 2 ohms connected in series with a capacitance of 6F. Calculate the discharging time constant. |
| A. | 3 |
| B. | 1 |
| C. | 12 |
| D. | 8 |
| Answer» D. 8 | |
| 28. |
A capacitor is charged to a voltage of 400V and has a resistance of 20ohm. Calculate the initial value of charging current. |
| A. | 10A |
| B. | 0A |
| C. | Infinity |
| D. | 20A |
| Answer» E. | |
| 29. |
If one plate of a parallel plate capacitor is charged to positive charge the other plate is charged to? |
| A. | Positive |
| B. | Negative |
| C. | Positive or negative |
| D. | Not charged |
| Answer» C. Positive or negative | |
| 30. |
When the voltage across a capacitor increases, what happens to the charge stored in it? |
| A. | Increases |
| B. | Decreases |
| C. | Becomes zero |
| D. | Cannot be determined |
| Answer» B. Decreases | |
| 31. |
A circuit has a resistance of 5 ohm connected in series with a capacitance of 10F. Calculate the discharging time constant. |
| A. | 15 |
| B. | 50 |
| C. | 5 |
| D. | 10 |
| Answer» C. 5 | |
| 32. |
When will capacitor fully charged? |
| A. | When the voltage across its plates is half the voltage from ground to one of its plates |
| B. | When the current through the capacitor is a 1/√2 time its value |
| C. | When the supply voltage is equal to the capacitor voltage |
| D. | Never |
| Answer» D. Never | |
| 33. |
What happens to the current flow in a fully charged capacitor? |
| A. | Current flow stops |
| B. | Current flow doubles |
| C. | Current flow becomes half its original value |
| D. | Current flow becomes one-fourth its original value |
| Answer» B. Current flow doubles | |
| 34. |
What is the relation between current and voltage in a capacitor? |
| A. | I=1/C*integral(Vdt) |
| B. | I=CdV/dt |
| C. | I=1/CdV/dt |
| D. | I=Ct |
| Answer» C. I=1/CdV/dt | |
| 35. |
Calculate the current in the capacitor having 2V supply voltage and 3F capacitance in 2seconds. |
| A. | 2A |
| B. | 5A |
| C. | 6A |
| D. | 3A |
| Answer» E. | |
| 36. |
Calculate the energy in the 4F capacitor. |
| A. | 128kJ |
| B. | 1.28kJ |
| C. | 12.8kJ |
| D. | 1280J |
| Answer» D. 1280J | |
| 37. |
Calculate the voltage across the capacitor at t=0. |
| A. | 0V |
| B. | 10V |
| C. | 20V |
| D. | Infinity |
| Answer» B. 10V | |
| 38. |
Calculate the energy stored in the combination of the capacitors. |
| A. | 192kJ |
| B. | 1.92kJ |
| C. | 19.2kJ |
| D. | 1920J |
| Answer» D. 1920J | |
| 39. |
What is the voltage across the 2F capacitor? |
| A. | 240V |
| B. | 200V |
| C. | 220V |
| D. | 120V |
| Answer» E. | |
| 40. |
Calculate the voltage across the 6F capacitor. |
| A. | 120V |
| B. | 60V |
| C. | 40V |
| D. | 220V |
| Answer» D. 220V | |
| 41. |
If the switch is closed at t=0, what is the current in the circuit? |
| A. | 0A |
| B. | 10A |
| C. | 20A |
| D. | Infinity |
| Answer» C. 20A | |
| 42. |
What is the voltage across the 4F capacitor? |
| A. | 120V |
| B. | 60V |
| C. | 100V |
| D. | 220V |
| Answer» C. 100V | |
| 43. |
Calculate the total charge of the system. |
| A. | 200C |
| B. | 100C |
| C. | 300C |
| D. | 400C |
| Answer» D. 400C | |
| 44. |
What is the equivalent capacitance? |
| A. | 1.5F |
| B. | 0.667F |
| C. | 2.45F |
| D. | 2.75F |
| Answer» C. 2.45F | |
| 45. |
Calculate the charge in the circuit. |
| A. | 66.67C |
| B. | 20.34C |
| C. | 25.45C |
| D. | 30.45C |
| Answer» B. 20.34C | |
| 46. |
Calculate the voltage across the 1F capacitor. |
| A. | 33.33V |
| B. | 66.67V |
| C. | 56.56V |
| D. | 23.43V |
| Answer» C. 56.56V | |
| 47. |
Calculate the voltage across the 2F capacitor. |
| A. | 33.33V |
| B. | 66.67V |
| C. | 56.56V |
| D. | 23.43V |
| Answer» B. 66.67V | |
| 48. |
The current equation for the given circuit is? |
| A. | a |
| B. | b |
| C. | c |
| D. | d |
| Answer» B. b | |
| 49. |
Calculate di(0)/dt if the switch is closed at t=0. |
| A. | -9.9A/s |
| B. | -10A/s |
| C. | 0A/s |
| D. | -0.1A/s |
| Answer» E. | |
| 50. |
Calculate d²i(0)/dt² from the given circuit. |
| A. | 10⁻⁶A/s² |
| B. | 10⁻³A/s² |
| C. | 10⁶A/s² |
| D. | 10³A/s² |
| Answer» C. 10⁶A/s² | |