2. Solve this binary equation. Answer in a decimal number form = A. 42 B. 54 C. 15 D

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1 Electronics Practice Test By David Scott, Manfred Brancard and Gary Troutman 1. A few capacitors are in parallel. Calculate the total capacitance. The capacitor values are 1uF, 2uF, 3uF, and 4uF. The total capacitance is: A. 10 uf B. 5 uf C. 1 uf D..01 uf 2. Solve this binary equation. Answer in a decimal number form = A. 42 B. 54 C. 15 D An Oscilloscope reads 10 volts peak to peak. What is the RMS voltage? A..707 VRMS B VRMS C VRMS D VRMS 4. In a capacitive circuit: A. Voltage leads current by 180 degrees B. Current leads voltage by 90 degrees C. Voltage leads current by 90 degrees D. Current leads voltage by 180 degrees 5. A heating element in an infant incubator uses 90 Watts of power and has a resistance of 1 kω. Calculate the current through the heating element. A..09 milliamps B..300 Milliamps C. 300 milliamps D. 9 milliamps 6. A Triac is used to switch A. DC power B. AC power C. AC or DC power D. FET gate current 7. Waveforms on an EEG Monitor are temporarily stored in: A. ROM B. RAM C. EPROM D. EEPROM 8. A GFCI normally has a trip point of A. 2 ma B. 3 ma C. 4 ma D. 6 ma 9. The IEEE standard for Ethernet communication: A B C D

2 10. Which one of these has the longest wavelength in the light spectrum: A. Violet Light B. Yellowish-Green Light C. Orange Light D. Dark Red Light 11. A Nicad battery normally has: A. 1.3 V per cell B. 1.2 V per cell C. 1.5 V per cell D. 1.0 V per cell 12. A transformer has 1968 primary windings and 492 secondary windings (4:1) and the input current is 1 amp. Output current is? A. 250 ma B. 4 A C. 500 ma D. 2 A 13. Calculate the total resistance of these resistors in parallel. 100 ohm, 3K ohm, 10K ohm. A ohms B ohms C. 95 ohms D. 100 ohms 14. Convert this number to decimal 4AF. A B C D What would the inputs have to be on a 3 input OR gate to get a low out? A. All low B. All high C. 2 lows 1 high D. 2 high 1 low

3 16. What inputs would be needed on the gate above to get a low output? A. high and high B. low and low C. low and high D. it can t have a low output 17. Checking a good transistor with a digital multimeter between C & E, it should read= A. 2 shorts B. 2 opens C..7V D. Short and open 18. Calculate the total inductance of two 40mH inductors in parallel. A. 20 mh B. 80 mh C. 40 mh D. 60mH 19. If a 4AH battery were replaced with a 2 AH with the same voltage rating, what would the result be? A. Shorter run time. B. Longer run time C. Same run time D.It would overheat the charging circuit 20. What type of filter is this? A. High Pass B. Low Pass C. Band Pass D. Impedance matching

4 The above circuit gives the normal operating voltages. Answer questions below using the above schematic drawing. 21. If VE= 40mVolts, VC=12 Volts, VB 700 mvolts. What is the defect? a. Open transistor base to emitter b. Open transistor collector to emitter c. Open transistor collector to base d. R2 is open 22. If VB=.105 volts, VC= 12 volts, VE=.105 in the circuit above, what is the defect? a. Open transistor base to emitter b. Shorted transistor base to emitter c. Open transistor collector to base d. C3 is open 23. If VB= 0.69 Volts, VE= 3 mv, VC= 3.2 V in the circuit above, what is the defect? a. Shorted C3 b. Open collector c. Open R1 d. Shorted R3 24. The normal output voltage at R5 is 550 mv peak. If the output voltage is only 250 mv, but the DC voltages at the transistor leads are normal, what is the defect? a. Open collector emitter of the transistor b. Leaky C3 c. Shorted R1 d. Open C2

5 25. What kind of amplifier set up is this in the drawing above? a. Common Collector b. Common Base c. Common Emitter d. Gate follower A. B.

6 C. D. E.

7 F. Please use the drawings above for questions Which drawing is a comparator a. A b. B c. C d. D e. E f. F 27. Which one of the drawings is a voltage follower? a. A b. B c. C d. D e. E f. F 28. Which one of the drawings is a differentiator? a. A b. B c. C d. D e. E f. F 29. Which one of the drawings is a non-inverting amplifier? a. A b. B c. C d. D e. E f. F

8 30. Determine the output voltage of the op-amp in schematic F above, if C2 has a short. a. 1.5 V b. 1 V c. 0 V d. 3.7 V 31. Which of the following is the unit of measure for capacitance? a. Henrys b. Farads c. Working volts d. Coulombs 32. Which of the following is the protocol that provides communication across interconnected networks? a. CSMA/CD b. SMTP c. TCP/IP d. Routing table 33. Which of the following is defined as volatile memory? a. ROM b. Flash c. Stable d. RAM 34. Which of the following is best determined by using an oscilloscope? a. The relationship between AC and DC in a circuit. b. The amount of AC current in a circuit. c. The amplitude of a DC signal. d. The voltage dropped across a resistor. 35. Which of the following is the objective of a band-pass filter? a. Allow a range of frequencies between an upper and lower cutoff point to pass through. b. Allow a range of frequencies below a upper cutoff frequency to pass through. c. Allow a range of frequencies above a lower cutoff frequency to pass through. d. Allow a range of frequencies above an upper cutoff frequency and below a lower cutoff frequency to pass through. 36. Which of the following is the equivalent resistance of two 20 Ohm resistors in parallel in series with a 10 Ohm resistor? a. 30 Ohms b. 15 Ohms c. 50 Ohms d. 20 Ohms 37. In order for a basic power supply to operate correctly, which of the following is true? a. The ttransformer must follow the regulator. b. The rectifier must follow the filter. c. The rectifier must follow the transformer. d. The regulator must be before the filter.

9 to the minus 6 power is the prefix for which of the following? a. Milli b. Mega c. Micro d. Pico 39. Which of the following occurs when batteries are connected in series? a. The current capability increases. b. The voltage provided will increase. c. The smaller battery will explode. d. The voltage provided will decrease. 40. The decimal number 255 is equivalent to which of the following Hexadecimal numbers? a. AA b. 100 c. FF d. FA 41. Which of the following inputs to the circuit below will produce a one on the output? A B C D a b c d A B C Output D 42. In a circuit containing a 1 uf capacitor and a 1 megohm resistor, which of the following is the amount of time needed for the capacitor to fully charge? a.5 seconds b.0.1 seconds c.0.5 seconds d.1 second

10 43. If R1 in the circuit below becomes shorted, which of the following will result? a. Lamps X1 and X2 will not glow. b. Lamps X1 and X2 will glow brighter. c. Lamps X1 and X2 will glow dimmer. d. Both lamps will burn out. 44. A circuit you are troubleshooting has developed a short. Which of the following would you expect to see? a. An increase in current drawn by the circuit. b. An increase in resistance. c. A decrease in the current drawen by the circuit. d. A decrease in voltage. 45. Which of the following is the frequency of a sine wave with a period of 8.3 milli seconds? a. 60 Hz b. 120 Hz c. 100 Hz d. 240 Hz 46. For a component with a negative temperature coefficient, which of the following would occur? a. The value of the component would increase with an increase in temperature. b. The value of the component would not change. c. The value of the component would decrease with an increase in temperature. d. The value of the component would decrease with a decrease in temperature.

11 12 15 V IN GROUND NOTE: Refer to the circuit above for questions 47 through 51. The normal operating voltages for this circuit are: VCE= 6.9 V, VE = 8.1 V, VR2 = 8.8 V. The output is taken from C Which of the following is the correct value for VC? a. 8.8 V b. 15 V c. 6.1 V d. 0 V 48. If VB = 0 V, which of the following would be the most likely circuit problem? a. Q1 open collector to emitter. b. R3 shorted. c. Q1 shorted base to emitter d. R2 shorted. 49. Which of the following is the correct value for VBE? a. 8.1 V b. 0.7 V c. 8.8 V d. 1.2 V

12 50. Assume there is a 10 millivolt peak-to-peak sine wave on the input. If C2 shorted, which of the following would be the most likely result? a. There would be no output. b. You would measure only an AC voltage at the output. c. You would measure an AC signal riding on an unknown DC voltage. d. You would measure an AC signal riding on 8.1 volts 51. Assume VE measured 8.8 volts. Which of the following would be the most likely problem? a. Open R2. b. Shorted C1. c. Base to emitter short on Q1 d. Collector to emitter short on Q Which of the following is the correct voltmeter reading for the circuit shown below? a. 2 volts. b. 10 volts. c. 4 volts. d. 6 volts.