Electronic Principles A transformer has a primary voltage of 120 V rms and a secondary voltage of 25 V rms. If the secondary current is 1A rms, what is the primary current? 300 mA None of these 200 mA 208 mA 7.8 mA 300 mA None of these 200 mA 208 mA 7.8 mA ANSWER DOWNLOAD EXAMIANS APP
Electronic Principles An intrinsic semiconductor has some holes in it at room temperature. What causes these holes? None of these Doping Free electrons Valence electrons Thermal energy None of these Doping Free electrons Valence electrons Thermal energy ANSWER DOWNLOAD EXAMIANS APP
Electronic Principles Which one of the following statements most accurately reflects the nature of ac power? The current in an ac circuit flows in one direction at a steady level The current in an ac circuit changes direction periodically The current in an ac circuit flows in one direction, but changes value periodically The current in an ac circuit flows in two directions at the same time None of these The current in an ac circuit flows in one direction at a steady level The current in an ac circuit changes direction periodically The current in an ac circuit flows in one direction, but changes value periodically The current in an ac circuit flows in two directions at the same time None of these ANSWER DOWNLOAD EXAMIANS APP
Electronic Principles Which one of the following principles best describes the basic operation of a generator? None of these Like magnetic poles attract; unlike poles repel Like magnetic poles repel; unlike poles attract Current flowing through a conductor generates a magnetic field Current is induced in a conductor that is moving through a magnetic field None of these Like magnetic poles attract; unlike poles repel Like magnetic poles repel; unlike poles attract Current flowing through a conductor generates a magnetic field Current is induced in a conductor that is moving through a magnetic field ANSWER DOWNLOAD EXAMIANS APP
Electronic Principles A high-pass filter: None of these passes lower-frequency signals and reduces higher-frequency signals increases the level of all frequencies by a significant amount passes higher-frequency signals and reduces lower-frequency signals has no effect on ac signals None of these passes lower-frequency signals and reduces higher-frequency signals increases the level of all frequencies by a significant amount passes higher-frequency signals and reduces lower-frequency signals has no effect on ac signals ANSWER DOWNLOAD EXAMIANS APP
Electronic Principles What is the turns ratio of a power transformer that shows 50 V at its secondary winding when you apply 150 V to its primary winding? 3 43922 2 43891 None of these 3 43922 2 43891 None of these ANSWER DOWNLOAD EXAMIANS APP
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