Electronics Engineering Review Part 1 Term Test PDF

Republic of the Philippines **TECHNOLOGICAL UNIVERSITY OF THE PHILIPPINES - TAGUIG CAMPUS** BOARD OF ELECTRONICS ENGINEERING ELECTRONICS ENGINEERING REVIEW PART 1 TERM TEST Tuesday, November 26, 2024 Time: 4:30 PM ======================================== \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_...

Republic of the Philippines **TECHNOLOGICAL UNIVERSITY OF THE PHILIPPINES - TAGUIG CAMPUS** BOARD OF ELECTRONICS ENGINEERING ELECTRONICS ENGINEERING REVIEW PART 1 TERM TEST Tuesday, November 26, 2024 Time: 4:30 PM ======================================== \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ **ELECTRONICS ENGINEERING** **REVIEW 3** **[INSTRUCTION:]** Answer the following questions/problems by shading the right letter only at the back with the corresponding number. Use pencil or ballpen. Use the back of the questionnaires for your scratch and solution. No need for extra papers. Strictly no erasures allowed in shading. Any form of cheating will subject to disciplinary action. 1. The time taken by an alternating voltage, v = 100sin240πt to reach 50V for the first time ---- -------- ---- -------- a. 358 μs b. 695 μs c. 358 ms d. 695 ms ---- -------- ---- -------- 2. A 2 kohm resistor is in series with a 0.015 uF capacitor across a 15 kHz ac source. What is the magnitude of the phase angle? ---- ------- ---- ------- a. 19.5° b. 26.5° c. 32.5° d. 44.5° ---- ------- ---- ------- 3. A waxed paper capacitor has two parallel plates, each of effective area 800 sq. cm. If the capacitance of the capacitor is 4425 pF, determine the effective thickness of the paper if its relative permittivity is 2.5. ---- -------- ---- -------- a. 0.2 mm b. 0.4 mm c. 0.2 cm d. 0.4 cm ---- -------- ---- -------- 4. Determine the effective voltage of v = 100sin120πt. ---- --------- ---- --------- a. 31.80 V b. 35.35 V c. 70.71 V d. 90.00 V ---- --------- ---- --------- 5. A parallel plate capacitor has the following values: k=81; d=0.025 inches; A=6 square inches. What is the capacitance of the capacitor? ---- ---------- ---- ---------- a. 4372 pF b. 437.2 pF c. 4.372 pF d. 43.72 pF ---- ---------- ---- ---------- 6. Three capacitors having a capacitance equal to 2F, 4F and 6F are connected in parallel. Calculate the effective parallel. ---- ------ ---- ------ a. 10 F b. 11 F c. 12 F d. 13 F ---- ------ ---- ------ 7. Capacitances 1 µF, 3µF, 5µF and 6µF are connected in parallel to a direct voltage supply of 100 V. Determine the total charge. ---- -------- ---- -------- a. 0.1 mC b. 0.6 mC c. 1.5 mC d. 1.8 mC ---- -------- ---- -------- 8. A current i=0.32t A flows through a 150 mH inductor. Find the energy stored at t=4ms. ---- ----------- ---- ----------- a. 0.123 J b. 1.229 J c. 12.288 nJ d. 122.88 nJ ---- ----------- ---- ----------- 9. If ten resistors of equal value were wired in parallel, the total resistance would be: ---- -------- ---- -------- a. 10 / R b. R / 10 c. 10 x R d. 10 + R ---- -------- ---- -------- 10. For the periodic waveform shown in figure below, determine the frequency. ---- --------- ---- --------- a. 62.5 Hz b. 82.5 Hz c. 625 Hz d. 825 Hz ---- --------- ---- --------- 11. In series R-L circuit the p.d. across the resistance R is 12 V and the p.d across the inductance L is 5V. Find the supply voltage. ---- ------- ---- ------- a. 7.0 V b. 8.5 V c. 13 V d. 17 V ---- ------- ---- ------- 12. The force between two charges is 120 N. If the distance between the charges is doubled, the force will be ---- ------ ---- ------ a. 60 N b. 30 N c. 40 N d. 15 N ---- ------ ---- ------ 13. The electric field intensity at a point situated 4 meters from a point charge is 200 N/C. If the distance is reduced to 2 meters, the field intensity will be ---- --------- ---- ---------- a. 400 N/C b. 600 N/C c. 800 N/C d. 1200 N/C ---- --------- ---- ---------- 14. A point charge of 5 nC is located at the origin. If 𝑉=2𝑉 at (0,6,−8) find the potential at 𝐴(√13,146.31°,6). ---- ------- ---- ------- a. 2.9 V b. 3.9 𝑉 c. 4.9 𝑉 d. 5.9 𝑉 ---- ------- ---- ------- 15. Considering a general-purpose carbon-composition type resistor, which of the following will be true? a\) A 2W resistor will be larger physically than a 1 W resistor. b\) A 2 W resistor will have 2 color bands while a 1 W resistor will have a single color band. c\) A 2 W resistor will be more precise than a 1 W resistor. d\) A 2 W resistor will automatically have larger resistance than a 1 W resistor. 16. The lines of force due to charged particles are a\) always straight b\) always curved c\) sometimes curved d\) none of the above 17. The electric field at a point situated at a distance d from straight charged conductor is a\) proportional to d b\) inversely proportional to d\^2 c\) inversely proportional to d d\) none of the above 18. Which of the following resistor is the best to use in terms of accuracy and precision. a\) a carbon-composition resistor having 4 color bands the last color being silver b\) a carbon-composition resistor having 4 color bands the last color being gold c\) a film-type resistor having 5 color bands the last color being violet d\) a film-type resistor having 5 color bands the last color being red 19. Which of the following resistor is arranged correctly from lowest to highest resistance? a\) 47RM, 4M7K, K47, R47 b\) R47, 47RM, K47, 4M7K c\) 4M7K, R47, 47RM, K47 d\) R47, K47, 4M7K, 47RM 20. Capacitance increases with \_\_\_\_\_\_\_\_ a\) Increase in plate area b\) Decrease in plate area c\) Increase in distance between the plates d\) Increase in density of the material 21. Which of these statements is true? a\) Q only b\) R only c\) Both Q and R d\) Neither Q nor R 22. The total voltage drop across a series of capacitors is \_\_\_\_\_\_\_\_\_\_ a\) The voltage drop across any one of the capacitors b\) The sum of the voltage drop across each of the capacitors c\) The product of the voltage drop across each of the capacitors d\) Zero 23. Which of the following is true regarding air-core coils? a\) also called ferromagnetic-core coils b\) less efficient than iron-core coils c\) used mostly for RF circuits d\) has high inductance to weight ratio 24. Which of the following is true/correct regarding induced voltage in a coil? a\) present only when there is a change in current b\) it is inversely proportional to inductance since inductance opposes change in current c\) both present only when there is a change in current and it is inversely proportional to inductance since inductance opposes change in current d\) neither present only when there is a change in current nor it is inversely proportional to inductance since inductance opposes change in current 25. Which of the following statement is FALSE? a\) coils can only be connected in series and never in parallel since magnetic flux is always additive b\) coils can store energy c\) coils operates differently for AC and DC d\) none of the above 26. When inductances are connected in series, the equivalent inductance is \_\_\_\_\_\_\_\_\_\_\_\_ the largest individual inductance. a\) Greater than b\) Less than c\) Equal to d\) Not related to 27. The effect of connecting an additional parallel load to an electrical supply source is to increase the a\) resistance of the load b\) voltage of the source c\) current taken from the source d\) p.d. across the load 28. "Y" networks are also known as....... a\) T networks b\) Bilateral networks c\) Imaginary networks d\) Hybrid networks 29. Two resistors are in parallel. Resistor A carries twice the current of resistor B, which means that: a\) the voltage across B is twice that across A b\) the voltage across A is twice that across B c\) A has half the resistance of B d\) B has half the resistance of A 30. What determines if resistor connections are in series, parallel, or series--parallel? a\) the voltage source b\) the power source c\) resistance d\) current flow 31. Which of the following has the same connection as the so called π -- network of resistors? a\) star-network b\) wye-network c\) delta-network d\) alpha-network 32. Which of the following is true? a\) Current-divider rule can be applied to two resistors in series. b\) Current-divider rule can be applied to two resistors in parallel. c\) Current-divider rule can be applied to either two resistors in series or two resistors in parallel. d\) Current-divider rule cannot be applied to either two resistors in series or two resistors in parallel. 33. If two equal-value inductors are connected in parallel, what is their total inductance? a\) Twice the value of one inductor b\) The same as the value of either inductor c\) The value of one inductor times the value of the other d\) Half the value of one inductor 34. Refer to figure. This shows what type of coil connection? a\) series-aiding b\) series-opposing c\) parallel-aiding d\) parallel-opposing 35. Which of the following will be true about his given circuit? a\) Q1+Q2+Q3 = QT b\) V1+V2+V3 = VT c\) C1+C2+C3 = CT d\) All of the above 36. Inductors are also called.... a\) condenser b\) reflector c\) coil d\) all of the above 37. Inductance can be defined as the ability of a device/component to oppose which of the following? a\) current b\) voltage c\) change in current d\) change in voltage 38. Which of the following statements is true about resistor? a\) P only b\) Q only c\) Both P and Q d\) Neither P nor Q 39. Why is ac current transfer more effective than dc current transfer over long distances? a\) due to the height of power lines b\) due to the use of ac generators c\) due to step-up and step-down transformers reducing I\^2R losses d\) due to very high voltages 40. Which of these waveforms is an alternating waveform? a\) A only b\) C only c\) C and D d\) B, C , and D 41. What do you mean by root-mean-squared (rms) value? a\) it is the average value b\) it is the effective value c\) it is the value that causes the same heating effect as a dc-voltage d\) it is the effective value or it is the value that causes the same heating effect as a dc-voltage 42. Which of the following is represented as imaginary number in analyzing AC circuits? a\) reactance b\) conductance c\) resistance d\) both reactance and conductance 43. 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 + j150 Ω b\) Z = 47 -- j150 Ω c\) Z = 197 Ω d\) Z = 103 Ω 44. Which of the following is represented as positive imaginary number? a\) resistance b\) conductance c\) inductive reactance d\) capacitive reactance 45. In an inductive circuit, the voltage\_\_\_\_\_\_\_ the current? a\) Leads b\) Lags c\) Is greater than d\) Is less than 46. Which of the following statements is true if the frequency decreases in the circuit in a series RL circuit? a\) The phase angle decreases. b\) VR decreases. c\) IT decreases. d\) VS decreases 47. In a parallel circuit, with any number of impedances, the voltage across each impedance is? a\) The same for all impedances b\) Is divided equally among all impedances c\) Is divided proportionally across all impedances d\) Is zero for all impedances 48. In an impedance parallel network, the reactive component will \_\_\_\_\_\_\_\_\_\_\_\_ the voltage by 90 degrees. a\) Lead b\) Lag c\) Either lead or lag d\) Depends on the circuit 49. Which of the following is not an example of true power? a\) Power that heats a resistor. b\) Power radiated from an antenna. c\) Power in a capacitor. d\) Heat loss in a feed line. 50. If the current and voltage are 90 degrees out of phase, the power factor will be? a\) 0 b\) Infinity c\) 1 d\) Insufficient information provided 51. Which of the following is true about power factor? a\) it is expressed usually in degrees b\) it can be expressed in radian c\) it is a unitless quantity d\) both it is expressed usually in degrees and it can be expressed in radian 52. Power that is measured in volt-amperes is called a\) real power b\) true power c\) reactive power d\) apparent power 53. In an inductive circuit, when the XL value increases, the circuit power factor? a\) Increases b\) Decreases c\) Remains the same d\) Becomes zero 54. In the figure shown, which of the following best describes current direction? a\) clockwise b\) counterclockwise c\) in both directions at the same time d\) 50% of the time clockwise and 50% of the time counterclockwise 55. How does a coil react to AC? a\) As the amplitude of the applied AC increases, the reactance decreases b\) As the amplitude of the applied AC increases, the reactance increases c\) As the frequency of the applied AC increases, the reactance increases d\) As the frequency of the applied AC increases, the reactance decreases 56. This V-I relation shown is for a...... a\) resistor b\) inductor c\) capacitor d\) either inductor or resistor 57. Advantage(s) of ac over dc a\) economically produced b\) transmission of ac is more efficient c\) ac voltages can be easily changed d\) all of the above 58. Which of the following is true/correct about sinusoidal waveforms? a\) Peak value is equal to the instantaneous value at π/4 b\) Peak value is equal to the instantaneous value at π2 c\) Peak value is usually twice the peak-to-peak value. d\) Peak value is usually half of the peak-to-peak value. 59. Peak value divided by the rms value gives us? a\) Peak factor b\) Crest factor c\) Both peak and crest factor d\) Neither peak nor crest factor 60. Which of the following is sometimes called as the DC value of a waveform? a\) RMS value b\) effective value c\) average value d\) any of the above is correct 61. Electrostatic field is \_\_\_\_\_\_\_\_\_\_\_ a perfect conductor. a\) same inside b\) infinite inside c\) zero inside d\) none of these 62. Potential is \_\_\_\_\_\_\_\_\_\_\_ a perfect conductor a\) same inside b\) infinite inside c\) zero inside d\) none of these 63. Permeability of vacuum is given as \_\_\_\_\_\_\_\_\_\_ a\) [4 × 10^ − 7^ *H**m*]{.math.inline} c\) [4 × 10^ − 9^ *H**m*]{.math.inline} 64. Electric flux density \_\_\_\_\_\_\_\_\_\_ medium a\) depends on b\) independent of c\) both a and b d\) none of these 65. What is the force exerted by a stationary charge when it is placed in a magnetic field? a\) zero b\) Minimum c\) maximum d\) Depends on the strength of the magnetic field 66. In a region of constant potential, a\) The electric field is zero b\) There can be no charge inside the region c\) Both a and b d\) The electric field is uniform 67. There will be force of attraction between two current-carrying conductors if the currents are in \_\_\_\_\_\_\_\_\_\_\_\_ direction. a\) same b\) opposite c\) none of these d\) cannot say 68. Magnetic flux density is the same as \_\_\_\_\_\_\_\_\_\_\_ a\) magnetic induction b\) magnetic field strength c\) both a and b d\) none of these 69. Total flux passing through a closed surface held in a magnetic field is \_\_\_\_\_\_\_\_\_\_. a\) infinity b\) zero c\) unity d\) none of these 70. The direction of electric field due to positive charge is a\) away from the charge b\) towards the charge c\) both a and b d\) none of the above **\...end of exam\...**