CORRECT ANSWERS COMPLETE
TELECOMMUNICATIONS STUDY GUIDE
●● How much current can be lethal?
Answer: 50-150 milliamperes
●● How much more DC than AC does it take to freeze a body to a
conductor?
Answer: 5 times: 12 ma AC, 60 ma DC
●● What are three types of burns?
Answer: 1) Electrical, 2) Arc, 3) Thermal Contact
●● What are three well-known examples of electrical protection devices
Answer: 1) Fuse, 2) Circuit Breakers, 3) Ground-Fault Circuit
Interrupters (GFCIs)
●● Never use ____ or ____ to extinguish an electrical fire because they
are electrically conductive substances.
Answer: water, foam
,●● What are the 4 steps that should be taken in the case of an electrical
fire?
Answer: 1) de-energize, 2) call the fire department, 3) control / put out
the fire, 4) report fire
●● Schematic diagrams are drawn so that the date or signal flows
through the circuit from ____ to ____.
Answer: left, right
●● What are the two methods to troubleshoot a circuit?
Answer: 1) trial and error, 2) logical procedure
●● What are the four steps to troubleshooting a circuit?
Answer: 1) Analyze the circuit, 2) Check the setup, 3) Calculate and
measure values, 4) Check the results.
●● What are three characteristics of an open?
Answer: 1) infinite resistance, 2) no circuit current, 3) measure applied
voltage
●● What are three characteristics of a short?
Answer: 1) no resistance, 2) increases circuit current, 3) measures 0
voltage
, ●● What are the three characteristics of a changed value?
Answer: 1) resistance increases or decreases, 2) increases or decreases
circuit current, 3) measures voltage other than calculated
●● What is a representation of AC voltage or current?
Answer: The sine wave
●● ____ is determined by the number of cycles that occur in one second.
Answer: Frequency
●● What is the basic unit of measurement for frequency?
Answer: the Hertz (Hz)
●● ____ is the length of time required to complete one cycle of an AC
sine wave.
Answer: Period
●● The symbol for period is ____?
Answer: T
●● Time is expressed as a ____.
Answer: decimal part of a second