Telecommunication Wiring Questions

Transcription

1 Telecommunication Wiring Questions 1. is the process of modifying a carrier frequency in rhythm to the audio frequency. A, Modulation B. Amplitude C. Change of phase D. Interference 2. is the property of a circuit that causes an opposition to any change of current within the circuit. A. Reactance B Inductance C Electrons is the property of an electrical circuit that limits the current. A. Voltage B. Capacitance C. Inductance D. Resistance 4. is the name given to the total opposition to the flow of electrical energy in a circuit and is the result of a combination of resistance, inductance, and capacitance. A. Current B Voltage C Impedance S. the electrical path between equipment, results in a difference in potential (voltage) between the source and destination equipment. A. Source impedance B. Z load C. Ground impedance D. Ground loop 6. A is used to test the efficiency of fiber, which determines the loss in decibels of the light signal and the length of the cable. A. Voltage Ohm Meter (VOIYI) B Time Domain Reflectometer (TDR) C Optical Time Domain Reflectometer (OTDR) D Optical Source Reflectometer (OSR) 70

2 A capacitor has capacitance of 1, when a current of 1 ampere causes a voltage change across the capacitor, of 1 volt in 1 second. A. Farad; 1 volt in 1 second B. Resistor, 1 volt in 2 seconds C. Capacitor, 2 volts in 1 second D. Inductor I volt in 2 seconds 8. A capacitor is measured in A. Ohms B Amperes C Volts D Farads A SIN ratio of A. 20 to 22 B. 23 to 26 C. 27 to 31 D. 32 to 34 db is normal on telephone leased lines. 10. All electrical equipment must be electrically connected to to prevent an electrical potential from occurring between the equipment and ground and between pieces of equipment. A. Water B Metal C Wire D Ground 11. An advantage of fiber optic cabling, known as, is that fiber cables do not produce electromagnetic noise. nor are they affected by electromagnetic noise, such as crosstalk, echoing and ringing or static. A. Electromagnetic immunity B. Adaptability C. Bandwidth D. Signal loss 12. An isolation amplifier may be used as a possible solution to a problem. A. Single ground B Multiple pound C Ground loop D Multiple conductor 71

3 13. Another possible solution to the multiple ground problem is the use of an A. Isolation transformer B. Isolation transistor C, Isolation amplifier D. All of the above 14. Both and cross sectional areas determine the resistance of wires. A. Width B Length C Circumference D Height 15. Coaxial cable (commonly called coax) has characteristic impedance of 751;2 and 14 AWG. A. RG 6 B. RG II C, RG 58 D. RG Copper communication cable (NEC Article 800). such as twisted pair and coaxial cable should be supported at least from power cables unless the power cables are enclosed in a conduit or raceway. A. 8 feet B 2 feet C 5 feet D 10 feet 17. Current is expressed by the formula A. E B. P; I C. E F 1 D. All of the above 18. Fiber optic cables are permitted to be included in current carrying cables containing A. More than 600 volts B Less than 800 volts C Less than 600 volts D Less than 400 volts

4 19. For a communication cable located outside on the same pole or run parallel to power cable A. The communication cable must be located below the power cable B. The communication cable passing over a roof must maintain a minimum of an eight foot clearance above the roof of a flat top building C. The supply service cable having less than 750 volts running above or parallel to communication service drops must have a minimum clearance of 12" at any point in the scan D. All of the above 20. In a capacitor, the opposition to a change in voltage is called A. Resistance B Capacitance C Capacitive reactance D Impedance 1 1. Light in the form of photons of energy is transmitted down the fiber by A. Refraction B. Coating C. Clad D. Modes 22. Modal, material and waveguide are three main types of A. Reduction B Retraction C Dispersion D All of the above in fibers. 23. North American companies have established a frequency of Hz with a power level of dbm (1 milliwatts) A. 1004;0 B. 1004;1 C. 1004;2 D. 1004;4 24. Pairs of wires are usually twisted to reduce A. Deductive effects B Inductive effects C Signal clarity D Inductive reactance 73

5 25. Physical. data link, network, transport, session, presentation, and application are levels of the protocol. A. Open system organization (OSO) B. Open System Interconnection (OSI) C. International Standards Organization (ISO) D. None of the above 26. Shielded cable is subject to electromagnetic A. More B Less C Equal crosstalk interference and radiates less 27. Shielded cable overall is subject to crosstalk interference and radiates electromagnetic signal. A. Less, Beater B. Less, less C. Greater, less D. Greater, greater 28. Single mode, multimode, and step index are types of A. Electrical cables B Fiber cables C Electrical wire 29. The ratio is a communication measurement that indicated the ability of a circuit or electronic system to distinguish between noise, unwanted signals and the signal selected. A. Noise to signal B. Sound to noise C. Reflection to noise D. Signal to noise 30. The American Wire Gauge (AWG) represents a wire's A. Length B Voltage C Diameter D Area

6 31. The charge that is stored between capacitor plates wihich tends to oppose any charge in circuit voltage is called A. Dielectric B. Capacitive reactance C. Crosstalk D. Flux line The current and voltage in an inductor and a capacitor are phase with each other. A. 180 degrees B 60 degrees C 90 degrees D All of the above degrees out of 33. The electrical path between equipment called a, results in a difference in potential (voltage) between the source and the destination equipment. A. Ground loop B. Shorted loop C. All of the above D. None of the above 34. The installation and testing of cables should include the correct labeling of all wires and termination points, testing of each wire within an installation and polarity testing. A. Twisted pair B Single fiber C Coaxial D Twin axial shielded 35. The introduction of any unwanted signal into a system is called A. Signal power B. Cross talk C. Noise D. Power loss 36. The measure of electromotive force that forces current through a circuit is: A. Wavelength B Current C Baud 75

7 37. The rate at which digital pulses are transmitted is called rate, and is defined as bits per second or pulses per second and is directly related to frequency. A. Transmission B. Pulse C. Byte D. Baud 38. The relationship between voltage, current and resistance in a circuit is called A. Electromotive force (EMF) B Ohms law C Electron flow D All of the above 39. The resistance of Number I. wire A C2 B LI C CI D. None of the above ohms per 1000 ft ( -4,) 20' C. 40. The smaller the cross sectional area of the conductor, the the resistance for a given length, and the the conductor, the ereater the resistance for a given cross sectional area. A. Greater, greater B Longer, greater C Greater,!weer D Longer, longer 41. To reduce the effects of magnetic induction noise during installation, A. Shield cables B. Never run data cables and power cables together in a conduit C. Properly ground equipment and cables D. All of the above 42. Two point connection strategy has the advantage of being the most interconnection between host and service user devices, while having the disadvantages of A. Reliable; safety problems B Direct; the possible need to re-cable, increased costs, and propagation C Flexible; very complex line connections D Resilient; the need to locally attach to a CPU for a specific application or program 76

8 43. Voltage can be compared to water A. Temperature B. Pressure C. Force D. None of the above that causes water to flow in a poipe. 44. Zero transmission level (dbm0) equals (=)? A. Tested level (TLP) - actual level (dbm) B. Tested level (TLP) + actual level (dbm) C. Actual level (dbm - tested level (TLP) D. Actual level (dbm) + tested level (TLP) 77

9 1. A 2. B 3. D 4. C 5. D 6. C 7. A 8. D 9. B 10. D IL A C 14. B 15. B 16. B 17. A 18. C 19. D 20. C 21. D 22. C Telecommunication Wiring Answers 23, A 14. B 25. B B 28. B 29. D 30. C 31. B 32. C 33. A 34. A 35. C 36. D 37. D 38. B 39. A 40. C 41. D 42. B 43. B 44. C