Majorship tle-electronics
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The document is a practice test for electronics containing 65 multiple choice questions. It covers topics such as basic electronic components like resistors, capacitors, diodes, transistors; circuits; electricity; electronics; transformers; and applications of electronics. The questions test knowledge of properties of components, how components function in circuits, Kirchhoff's laws, and concepts in electricity and electronics. An answer key is provided at the end to check responses.
Majorship tle-electronics
- 1. Page 1 MAJORSHIP LET REVIEWER IN TLE PRACTICE TEST IN ELECTRONICS 1. It is an electronic device use to limit the flow of electric current. A. capacitor B. resistor C. transistor D. diode 2. It is an electronic device use to stow electric charge. A. resistor B. transistor C. diode D. capacitor 3. It is a solid state device use to amplify the small input signal to become large output signal. A. resistor B. transistor C. diode D. capacitor 4. It is the simplest solid state device which is use as rectifier. A. transistor B. diode C. resistor D. capacitor 5. It is a kind of electronic equipment use to measure resistance. A. Voltmeter B. Ohm meter C. Ammeter D. Wattmeter 6. It is a kind of diagram where all information its symbol and designation are emphasize. A. Electricity B. Schematic diagram C. Wiring diagram D. fish tailing diagram 7. It is a branch of physics which deals with the study of the behavior properties and control electrons in the circuit. A. Electricity
- 2. Page 2 B. Electronics C. Radio Mechanics D. Computer 8. It is a kind of circuit where there is a continuous flow of electric current. A. Close circuit B. Open circuit C. Short circuit D. Ground circuit 9. It is a process of removing unwanted copper from the PCB. A. Soldering B. Etching C. Boring D. Mounting 10. How much is the resistance of a 100 watts 120 volts light bulb? A. 1.44 ā¦ B. 14.4 ā¦ C. 144 ā¦ D. 1440 ā¦ 11. Commonly resistor is connected in a circuit to A. drop voltage B. drop reactance C. increase voltage D. increase reactance 12. If a given resistor has color coded value as brown, red, orange and gold, its nominal value is A. 123 ā¦ Ā± 5% B. 123 ā¦ Ā± 10% C. 12,000 ā¦ Ā± 5% D. 12,000 ā¦ Ā± 10% 13. When two resistors having different values are connected in parallel, their total resistance can be calculated as A. RT = N/2 B. RT = R1 + R2 C. 1/RT = 1/R1 + 1/R2 D. none of the above 14. The total resistance of the resistors connected in series with values such as 1.2 k ā¦ and 500 ā¦ is A. 1.7 k ā¦
- 3. Page 3 B. 1,700 ā¦ C. 352.94 ā¦ D. a and b 15. It is a property of circuit element which opposes any current change, and is measured in Henry, this is called A. Capacitance B. Inductance C. Resistance D. Conductance 16. The power transformer characterized with more number of turns at the primary than the secondary winding is a transformer known as A. step-down B. step-up C. auto-transformer D. isolating 17. Inductors L1 and L2 are in parallel with each other having the same values of 300mH. Their combined inductance is A. 150mH B. 600mH C. 0 D. none of the above 18. If a power transformer has NP of 1800 turns, NS of 74 turns and EP of 220 V, how much is the ES? A. 3 V B. 6 V C. 9 V D. 12 V 19. Capacitorās property which says how much charge can be stored units dielectric is referred to as A. Resistance B. Conductance C. Inductance D. Capacitance 20. A capacitor consists of two A. conductors separated by an insulator B. insulators separated by a conductor C. conductors alone D. insulators alone
- 4. Page 4 21. To combine capacitances in series. It is computed simply by A. 1/CT = 1/C1 + 1/C2 B. C = Q/V C. CT = C1 + C2 D. None of the above 22. The unit of measure of electrical current is A. Volt B. Ampere C. Ohm D. Watt 23. When capacitors are connected in parallel, their capacitances can be calculated as A. CT = C1 + C2 B. 1/CT = 1/C1 + 1/C2 C. C = Q/V D. None of the above 24. A capacitance of 0.02 ĀµF equals A. 0.02 X 10Ā¬Ā¬-12 F B. 0.02 X 10-6 F C. 0.02 X 106 F D. 200 X 10-12 F 25. When a semiconductor diodeās anode terminal is supplied with negative dc voltage and the cathode with positive dc voltage, the diode bias is A. Forward B. Reverse C. No bias D. More bias 26. When the arrow head on the electronic symbol of a semiconductor transistor is pointing inward, the type of transistor is A. NPN B. PNP C. NPNP D. PNPN D. Larger than a no. 8 copper wire 27. If 12 volts are applied to a certain lamp whose filament has a resistance of 3 ohms, the current flow through the lamp filament will be A. 4 amp
- 5. Page 5 B. 36 amp C. 8 amp D. 12 amp 28. If a copper wire becomes heated because of an excessive amount of current flowing through it, the resistance of the wire A. Decreases B. Increases C. Remains the same as when the wire is cold D. Becomes zero 29. To measure the current flowing through a circuit, connect an A. Ohm meter B. Ammeter C. Volt meter D. Meter in series with the circuit 30. In the laboratory, to verify the current in a resistor, _. A. an ammeter is connected in series with the resistor B. a voltmeter is connected in series with the resistor C. an ammeter is connected parallel to the resistor D. a voltmeter is connected parallel to the resistor 31. Which statement is true? a. An ammeter has negligible resistance. b. A voltmeter has negligible resistance. c. An ammeter measures voltage. d. A voltmeter measures current. 32. Kirchhoffās Current Law : nodes ; Kifchhoffās Voltage Law : a. junction b. loops c. meshes d. b and c 33. Kirchhoffās Laws are applicable to networks with series resistors. a. Always true b. Often time c. Sometimes true d. Never true 34. The conservation law that served as basis for Kirchhoffās Current Law is . a. conservation of charge
- 6. Page 6 b. conservation of energy c. conservation of mass d. conservation of quantum numbers 35. Which statement is true about Kirchhoffās Current Law? a. The sum of the currents entering the node is equal to that leaving the same node. b. The current in a conducting loop is the same for all resistors in the loop. c. The numerical sum of the currents entering a node is zero. d. The sum of the current over a loop is zero. 36. A capacitor and an inductor are electronic components that store electrical energy. How is an inductor different from a capacitor? a. An inductor is an electromagnet b. An inductor is made up of a coil of wire c. An inductor may be made into a capacitor d. An inductor stores energy in its magnetic field 37. Which of the following is NOT a function of a resistor in a circuit? I. It limits the flow of current II. It prevents short and overloading III. It regulates the voltage of circuit elements a. I only b. II only c. I and II d. I, II and III 38. Which of the following describes a step up transformer? Primary Coil Secondary Coil No. of Turns Voltage No. of turns Voltage 200 10 V 50 100 V 200 10 V 150 100 V 200 10 V 200 100 V 200 10 V 2000 100 V 39. How does a diode convert an AC signal to a DC signal? a. By filtering the flow of current in the circuit b. By allowing current to pass in one direction c. By resisting the flow of current in the circuit d. By regulating the flow of current in the circuit 40. Which of the following instrument is used to measure the amount of current flowing in an element in a circuit? a. ammeter
- 7. Page 7 b. ohmmeter c. tester d. voltmeter 41. A transformer has 250 turns in its secondary coil. The secondary voltage is 10 V. If the transformer is connected to a 220 V source, how many turns does the transformer have in its primary coil? a. 5500 b. 2500 c. 500 d. 11 42. Which of the following semiconducting device serves as an amplifier in a circuit? a. capacitors b. diodes c. integrated circuits d. transistors 43. A step up transformer is used by power plants to transmit electrical power at a very high voltage over a large distance. Why is this so? a. It is the cheapest way of transmitting electrical power. b. Because large amount of power requires large amount of voltage for transmission. c. Because high voltage transmission lines have almost zero resistance to the flow of current. d. Because current is small in high voltage transmission lines preventing significant waste of electrical energy. 44. Which of the following semiconducting device is generally used as an indicator when an appliance is turned on or off? a. Light emitting diodes b. Photodiodes c. Photoresistors d. Small lamps 45. Compared to the primary coil, the number of turns in the secondary coil of a step up transformer is _. a. less b. more c. the same d. infinite 46. What does a changing magnetic field in a coil of wire produce? a. An induced power b. An induced voltage
- 8. Page 8 c. An induced resistance d. An induced coil polarity 47. Why does alternating current replace direct current for general use? a. Alternating current has more power than direct current b. Alternating voltages are convenient to transform c. Generators always generate alternating current d. Alternating current is safer than direct current 48. How does the audio signal of television networks transmitted? a. By modulating the frequency of the wave b. By modulating the amplitude of the wave c By transforming it to an analog signal d. By transforming it to a digital signal 49. A fuse or a circuit breaker is always connected in series with the appliance or the circuit that it intends to protect when short or overloading happens. Why is this so? a. It is easier to connect a fuse in series than in parallel. b. Short and overloading always happen in series circuits. c. There is higher probability for overloading in parallel circuits. d. There is only one path for current to flow in a series connection. 50. In the laboratory, to determine the voltage across a resistor, . a. an ammeter is connected in series with the resistor b. a voltmeter is connected in series with the resistor c. an ammeter is connected parallel to the resistor d. a voltmeter is connected parallel to the resistor 51. Which statement is true? a. An ammeter has negligible resistance b. A voltmeter has negligible resistance c. An ammeter measures voltage d. A voltmeter measures current 52. Kirchhoffās Current Law : conservation of charge ; Kirchhoffās Voltage Law : a. conservation of mass b. conservation of energy c. conservation of quantum numbers d. b and c 53. Kirchhoffās Laws is applicable to networks containing any electrical elements. a. Always true b. Often time
- 9. Page 9 c. Sometimes true d. Never true 54. Kirchhoffās Voltage Law is applicable to networks containing . a. capacitors b. inductors c. potential and current sources d. resistors 55. Which statement is NOT true about Kirchhoffās Laws? a. The numerical sum of the voltage rise and that of the potential drop in a conducting loop are equal. b. The sum of the voltage rise and the voltage drop in a conducting loop is zero. c. The voltage across any resistor in a loop is always a voltage drop. d. The voltage across a voltage source is sometimes a voltage drop. 56. Compared to the primary coil, the number of turns in the secondary coil of a step down transformer is . a. less b. more c. the same d. infinite 57. How does the video signal of television networks transmitted? a. By modulating the frequency of the wave b. By modulating the amplitude of the wave c By transforming it to an analog signal d. By transforming it to a digital signal 58. Which of the following describes a step down transformer? Primary Coil Secondary Coil No. of turns Voltage No. of turns Voltage a. 50 100 V 200 10 V b. 150 100 V 200 10 V c. 200 100 V 200 10 V d. 2000 100 V 200 10 V 59. Which of the following instrument is used to measure the potential difference across an element in a circuit? a. Ammeter b. Ohmmeter c. Tester d. Voltmeter
- 10. Page 10 60. The amount of energy consumed by an appliance per unit time is indicated as the applianceās a. current b. power c. resistance d. voltage 61. Which of the following can be a function of a transistor in a circuit? a. Amplifies current or electric signals b. Limits the flow of current c. Stores electrical energy d. Regulates voltage 62. A battery has a voltage of 12 V. What does this mean? a. Both terminals of the battery have a 12 V electric potential. b. Both terminals of the battery have the same electric potential. c. One of the terminals of the battery is 12 V and the other is 0 V. d. One of the terminals of the battery is 12 V higher in electric potential than the other. 63. Which of the following device best demonstrates the concept that magnetism exerts a force on a moving charge? a. Diode b. Generator c. Motor d. Transformer 64. Which of the following can cause electric shock? a. Current and power b. Current and voltage c. Voltage and power d. Voltage and resistance 65. Which of the following can serve as a source of radio waves transmitted by telecommunications systems? a. Electromagnetic waves b. Nuclear reactions c. Electric circuits d. The sun
- 11. Page 11 Answer Key Maorship LET Reviewer - TLE Electronics 1. B 2. D 3. B 4. B 5. B 6. C 7. B 8. A 9. A 10. C 11. D 12. C 13. C 14. D 15. B 16. A 17. A 18. C 19. D 20. A 21. A 22. B 23. A 24. B 25. A 26. B 27. A 28. B 29. B 30. A 31. A 32. D 33. A 34. A 35. A 36. D 37. D 38. D 39. B 40. A 41. A 42. D 43. D 44. A 45. B 46. B 47. B 49. D 50. D 51. A 52. B 53. A 54. C 55. D 56. A 57. B 58. D 59. B 60. B 61. A 62. D 63. C 64. A 65. C