QUESTIONS AND CORRECT ANSWERS
ALREADY PASSED
◉ 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
◉ The formula for period is ____. Answer: T = 1 / f
◉ ____ is the distance from beginning to end of one complete cycle of
an AC sine wave. Answer: Wavelength
◉ The symbol for wavelength is ____. Answer: λ (lambda)
◉ Wavelength is expressed in ____ or ____. Answer: meters or
centimeters