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Which of the following applies to stopping a motor by electronically reversing the motor while it is still running in the forward

direction? dynamic braking regenerative braking plugging jogging Which of the following starters increases the voltage gradually as the motor starts? primary-resistance starter autotransformer starter wye-delta starter solid-state starter

Technician A says a reduced reduced-voltage starter is designed to apply full line voltage to the motor upon starting. Technician B says reduced-voltage starting produces a lower starting torque. Who is correct? Technician A only Technician B only both Technician A and Technician B neither Technician A nor Technician B

The foil pattern layout for a PC board shows: all the interconnecting terminal strip connections. the exact location of all the component parts. all necessary conductor routing required for the working circuit. all of these

Resist is any material which: acts like a resistor. offers resistance to the flow of current in a circuit. will resist the chemical reaction used to etch copper. all of these

When soldering on a PC board, the solder is always applied to: the tip of the soldering iron only.

both the tip of the soldering iron and the component lead. the junction of the lead and the terminal pad area. the laminate.

Cleaning the copper foil of a PC board prior to soldering: is only necessary if the foil appears dirty or dull. is only necessary if a rosin based flux is not used. is essential in all instances. both a and b

Nonvolatile memory loses all its information when power is removed. True False

The computing power of a computer is determined by its wattage rating. True False

All computers are able to get data into and out of memory at approximately the same speed. True False The input/output provisions for microprocessor-based systems are all basically the same. True False

Types of output devices include instrumental displays and actuators. True False

MS-DOS is an example of a programming language. True False

In any number system, the position of a digit that represents part of the number has a weighted value associated with it. True False To express a number in binary requires fewer digits than in the decimal system. True False The only true mathematical operation performed by a computer is division. True False

In a D flip-flop, the Q output is the same as the D input one clock pulse later. True Fals

Asynchronous is the term used to designate control by a clock pulse. True False Binary counters are usually constructed using XOR gates. True False

Technician A says the duty cycle of a pulse waveform is the percentage of the time the output is high. Technician B says the duty cycle of a pulse waveform is found by dividing the total ON time by the total OFF. Who is correct? Technician A only Technician B only both Technician A and Technician B neither Technician A nor Technician B

Which of the listed logic gates is considered to be a BASIC building block (basic logic gate) used i in logic diagrams? NAND OR NOR All of the above. Which of the listed conditions is an advantage of a PN diode over a vacuum diode?

Longer life. No warm up time. Less delicate. All of the above.

The type of feature afforded auxiliaries vital to the operation of propelling equipment, where automatic restart after a voltage failure would not create a hazard, is termed : low voltage protection high amperage protection low voltage release high amperage release

) The insulation resistance of electric equipment and machinery should be tested for the lowest normal insulation values : immediately after shutting down the machine every time the brush rigging is adjusted immediately after starting up the machine every 30 days whether the machine is in use or not

triac thyristor functions as a control device and is basically : two NPN transistors in parallel with a common base lead a diode in series with a temperature sensitive capacitor two back-to-back SCR's with a common gate lead a triode tube with an extra heavy grid element

The apparent power in a purely inductive circuit is also known as : true power lead power induced power reactive power

The unit of apparent power in a purely inductive circuit is called the : kva var

emf watt

The basic control action of a magnetic amplifier depends upon : variations in the load capacitance changes in inductance type of core material construction of the core Which of the listed conditions describes the effect on intrinsic semiconductor operation as a result of a temperature increase? Additional heat sinks will be required Conductivity will increase Conductivity will decrease Resistivity will increase (AMBALARE TERMICA)

Operational amplifiers, used primarily in analog circuits, are characterized by : high input impedance, high gain and low output impedance high input impedance, high gain and high output impedance low input impedance, low gain and high output impedance low input impedance, high gain and low output impedance

Which of the following expresses the relationship of the input and output frequencies in a full wave rectifier? The output frequency is the same as input frequency. The output frequency is one-half the input frequency. The output frequency is twice the input frequency. The output frequency is four times the input frequency.

To provide its unique characteristics to analog circuits, the operational amplifier is made up of a/ a/an : voltage amp, current amp and output amp input amp, power amp and output amp scaling amp, power amp and voltage amp differential amp, voltage amp and output amp

When replacing a power transistor fitted with a heat sink in a circuit, a coating of silicone grease is applied between the transistor case and the heat sink. This is done to : lubricate the transistor lubricate the heat sink aid in the removal of the heat sink provide maximum heat transfer

When a megohmmeter is being used to test insulation resistance, current leakage along the surface of the insulation is indicated by the megohmmeter's pointer : dipping toward zero then raising slowly continually rising as test voltage is applied kicking slightly down scale as voltage is applied fluctuating around a constant resistance reading

Which of the following actions can be carried out in order to prevent thermal runaway in a transistor? Increase the current through the collector-base junction. Install a heat sink. Shift the 'Q' point to increase collector current. Increase the potential difference between the emitter and the base.

Basic operating characteristics of the operational amplifier such as gain and stability are the function of its : differential input stage power output stage feedback circuit supply voltages

Which of the procedures listed could result in damaging a transistor beyond repair? Applying incorrect polarity to the collector circuit. Applying excessive voltage to the input circuit. Careless soldering which would overheat the transistor. All of the above.

Basically, a magnetic amplifier is a saturable reactor with the addition of :