Installer Technician Study Guide 2023

20 milliamperes is the same as ________. (Remember, 1 milliampere = 0.001 ampere.) - 0.02 amperes The orbital shell that has a maximum electron capacity of 18 electrons is the ___________ shell. - Third A semiconductor material - Has four valence electrons. The major factor for determining whether a particular element is a conductor, a semiconductor, or an insulator is - The number of electrons in the valence shell. Elements that are called conductors - Have very few valence electrons. The term voltage normally refers to - The measurement of the difference in potential between two charges. The ampere - Indicates how many coulombs pass a given point during 1 second. Electric current is actually produced by - The transfer of energy from valence electron to valence electron as a result of applied charges. What prevents the electrons that orbit an atom's nucleus at high speeds from breaking away from the nucleus due to centrifugal force? - The attraction between the positive nucleus and the negative electron. 5 kilovolts is the same as - 5 kV. To create an electromagnet, - Wrap a coil of insulated wire around an iron bar and pass an electric current through the wire. Magnetism - Was discovered when the Greeks noticed that magnetite always aligned itself in a north and south direction. In a magnetic material, - Where only some of the magnetic domains are pointing in the same direction, the magnetic field is weaker. The strength of an electromagnetic field is - Determined by the magnitude of the magnetomotive force (mmf). The magnetic field - Created by a straight piece of wire is weaker than that created by forming loops of wire. Flux lines - Always curve around through the body of the magnet to form complete loops. Magnetic poles that are ___________ will ____________ each other when those poles are near each other. - Alike, repel A permanent-magnet loudspeaker - Has a cone that moves back and forth in relation to the varying current of the original sound. The left-hand rule for electromagnetism in a wire states that - If you wrap the fingers of your left hand around the wire with your thumb pointing in the direction of the current flow, your fingers will be wrapped in the direction of the magnetic field. The recording head of a tape recorder is actually a(an) - Electromagnet. (-25) + (42) + (-62) + (20) = - -25 (-17) - (-34) = - 17 (17) x (-19) = - -323 -49/-7 = - 7 (20) / (-4) + (-2) x (-10) - (-2) x (7) = - 29 3 6/9 + 6 1/3 + 9 5/9 = - 19 5/9 4/7 x 9 4/11 = - 5 27/77 7 3/8 divided by 7 1/4 = - 1 1/58 13 X 0.123 = - 0.99999 0.5349 divided by 0.1420 = - 3. Which of the following is a true axiom? - When A = C and B = C, then A = B because both are equal to C, which supports the axiom: Quantities equal to the same quantity are equal to each other. Simplify and solve the equation: If E = IR then what is the formula for finding I? - E/R. The square of 7 = _____. - 49 The square root of 81 = _____. - 9 0.00004 = ______ x 10 to the power of ______. - 4, -5 (75 x 10^3)+(25 x 10^4) = ____. - 32.5 x 10^4 (480 x 10^-5) / (60 x 10^-3) = _____. - 8 x 10^-2 10 to the power of -3 has a metric prefix of ______. - Milli (250 x 10^-6) - (7 x 10^-5) = _____. - 180 x 10^-6 (75 x 10^3) + (2.5 x 10^4) = ____. - 100 x 10^3 What are the three basic elements of an electrical circuit? - A power source, a load, and the connecting conductors. The power source - Is the part of an electrical circuit that provides a difference of potential. The load - Is the part of the electrical circuit that uses the electrical energy provided by the power source to carry out some desired function. A conductor - Provides a path for the current flow from the power source to the load and from the load back to the power source. The metal that has the greatest conductance is - Silver. Normal current flow results - When the circuit operates properly and no damage occurs to the circuit components. Excessive current flow - Is often the result of the failure of a small part within a larger circuit. Direct current - Flow is continuous electron flow in the same direction. Which of the following is a correct definition for a type of circuit graphic? - A block diagram is a simplified outline of an electrical system that shows circuits or parts as rectangles and other shapes. A symbol - Is a simple line design used to represent a component or device in a schematic circuit diagram. Resistance - Doubles when the length of a conductor doubles. Load resistance - Is considered to be the total resistance when the source and wire resistances are very small.