Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Element 3
GROL
| Question | Answer |
|---|---|
| The product of the readings of an AC Voltmeter & AC ammeter is called? | Apparent Power |
| What is the basic unit of electrical power? | Watts |
| What is the term used to express the amount of electrical energy stored in an electrostatic field? | Joules |
| What device is used to store electrical energy in an electrostatic field? | Capacitor |
| What formula would determine the inductive reactance of a coil if frequency and coil inductance are known? | XL=2*pi*FL |
| What is the term for out-of-phase power associated with inductors and capacitors? | Reactive power |
| What determines the strength of a magnetic field around a conductor? | The amount of current |
| When induced currents produce expanding magnetic fields around cunductors in a direction that opposes the opposes the original magnetic field, is known as? | Lenz's Law |
| The opposition to the creation of magnetic lines of force in a magnetic circuit is know as? | Reluctance |
| What is meant by the term Back EMF? | A voltage that opposes the applied EMF. |
| Permeability is defined as? | The ratio of magnetic fulx density in a substance to the magnetizing force that produces it. |
| What metal is usually employed as a sacrificial anode for corrosion control purposes? | Zinc bar. |
| What is the relative dielectric constant for air? | 1 |
| which metal object may be least affected by galvanic corrosion when submerged in sea water? | Stainless steel propeller shaft. |
| Skin effect is the phenomenon where? | RF current flows in a thin layer of the conductor, closer to the surface, as frequency increases. |
| Corrosion resulting from electric current flow between dissimilar metals is called? | Galvanic corrosion |
| Which of these will be most useful for insulation at UHF frequencies? | Mica |
| What formula would calculate the total inductance of inductors in series? | LT= L1+L2..... |
| Good conductors with minimum resistance have what type of electrons? | Many free electrons |
| Which of the four groups of metals list below are the best low resistance conductors? | Gold, Silver, and Copper. |
| what is the purpose of a bypass capacitor? | It removes alternating current by providing a low impedance path to ground. |
| How would you calculate the total capacitance of three capacitors in parallel? | CT=C1+C2+C3..... |
| How might you reduce the inductance of an antenna coil? | Reduce the number of turns. |
| What are the two most commonly used for a a junction diode? | Maximum forward current an PIV (peak inverse voltage). |
| What limits the maximum forward current in a junction diode? | The junction temperature. |
| MOSFETs are manufactured with THIS protective device built into their gate to protect the device from static charges and voltages? | Zener diode. |
| What are the two basic types of junction field-effect transistors? | N-channel P-channel |
| A common emitter amplifier has? | More voltage gain than a common collector. |
| How does the input impedance of the field-effect transistor compare with that of a bipolar transistor? | An FET has high input impedance; a bipolar has low input impedance. |
| An AC ammeter indicates? | Effective (RMS) values of current. |
| By what factor must the AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to obtain the peak voltage value? | *1.414 |
| What is the (RMS) voltage of a common household electrical outlet? | 117-VoltsAC |
| What is the easiest voltage amplitude to measure by viewing a pure sing wave signal on an oscilloscope? | Peak-to-Peak |
| BY what factor must the voltage measured in an AC circuit, as indicated on the scale of an AC voltmeter, be multiplied to maintain the average voltage vaule? | *0.9 |
| What is the peak voltage of a common household electrical outlet? | 165.5 Volts |
| What is a sign wave? | A wave whose amplitude at any given instant can be represented by the projection of a point on a wheel rotating at a uniform speed. |
| How many degrees are there in one complete sine wave cycle? | 360 degrees. |
| What type of wave is made up of sine waves of the fundamental frequency and all the odd harmonics? | Square wave. |
| What is the description of a square wave? | A wave that abruptly changes back and forth between two voltage levels and stays at these levels for equal amounts of time. |
| What type of wave is made up of sign waves at the fundamental frequency and all harmonics? | Sawtooth wave. |
| What type of wave categorized by a rise time significantly faster than the fall time? | Sawtooth wave. |
| What is the term used to identify the AC voltage that would cause the same heating in a resistor as a corresponding value of DC voltage? | Root Mean Square. (RMS) |
| What happens to reactive power in a circuit that has both inductors and capacitors? | It alternates between electric and magnetic fields and does not dissapate. |
| Having the cross-sectional are of a conductor will what? | Double the resistance. |
| Which of the following groups is correct for listing common materials in order of descending conductivity? | Silver, Copper, Aluminum, Iron, and Lead. |
| How do you compute true power ( power dissipated in the circuit ) in a circuit where AC voltage and current are out of phase? | Multiply the apparent power by the power factor. |
| Assuming a power source to have a fixed value of internal resistance,maximum power will be transferred to the load when? | The load impedance equals the internal impedance of the source. |
| What value of series resister would be needed to obtain a full scale deflection on a 50 micro-amp DC meter with an applied voltage of 200 volts DC | 4 Mega-ohms. |
| Which of the fallowing Ohms laws formulas is incorrect? | I=R/E |
| If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor? | 100 Volts. |
| if a 100-ohm resistor is connected across 200 volts, what is the current through the resistor? | 2 amperes |
| If a current of 3 amperes flows through a resistor connected to 90 volts, what is the resistance? | 30 ohms |
| A relay coil has 500 ohm resistance, and operates on a 125 mili-amp. What value of resistance should be connected in series for it to operate 110 V DC? | 380 ohms |
| What is the Peak-to-Peak RF voltage on the 50 ohm output on a 100 watt transmitter? | 200 volts |
| What is the maximum DC or RMS voltage that may be connected across a 20 watt, 2,000 ohm resistor? | 200 volts |
| A 500-ohm, resistor and a 1500-ohm, 1-watt resistor are connected in parallel. What is the maximum voltage that can be applied across the parallel circuit without exceeding the wattage ratings? | 31.6 volts |
| What is the maximum current-carrying capacity of a resistor marked " 2000 ohms, 200 watts " ? | 0.316 amps |
| What is the most the actual transmit frequency could differ from the reading of for 462,100,000 Hz on a frequency counter with a time base accuracy <>+- 0.1ppm?` | 46.21 Hz |
| The second harmonic of 380 kilo Hz is? | 760 K Hz |
| What is the second harmonic of SSB frequency 4146 K Hz? | 8292 K Hz |
| What is the most the actual transmitter frequency could differ from a reading of 156,520,000 Hz on a frequency counter with a time base accuracy of +- 1.0ppm | 156.52 Hz |
| What is the most the actual transmitter frequency can differ from the reading 462,100,000 Hz on a frequency counter with a time base frequency of +-1.0ppm? | 462.1 Hz |
| At pi-3 radians, what is the amplitude of a sine-wave having a peak value of 5 volts? | +4.3 volts |
| At 150 degrees, what is the amplitude of a sine-wave having a peak value of 5 volts? | +2.5 volts |
| At 240 degrees, what is the amplitude of a sine-wave having a peak values of 5 volts? | -4.3 volts |
| What is the equivalent to the root mean square value of an AC voltage? | The DC voltage causing the same heating in a given resistor as the RMS AC voltage of the same value. |
| What is the RMS value of a 340-volt Peak-to-Peak pure sine-wave? | 120 volts AC. |
| What does the power factor equal in a RL circuit having a 60 degree phase angle between the voltage and the current? | 0.5 |
| If a resistance to which a constant voltage is halved, what power dissipation will result? | Doubled. |
| 746 watts, corresponding to the lifting of 550 pounds at the rate or one foot per second, is the equivalent of how much horse power? | 1 HP |
| In a circuit where the AC voltage and current are out of phase, how can the true power be determined? | By multiplying the apparent power * the power factor. |
| What does the power factor equal in an RL circuit having a 45 degree phase angle between the voltage and the current? | 0.707 |
| What does the power factor equal in a RL circuit having a 30 degree phase angle between the voltage and current? | 0.866 |
| What is the term for the time required for the capacitor in a RC circuit to be charged to 63.2% of the supply voltage? | One time constant |
| What is the meaning of the term (Time constant of an RC circuit) the time required to charge the capacitor in the circuit to? | 63.2% of the supply voltage. |
| What is the term for the time required for the current in a RL circuit to build up to 63.2% of the maximum value? | One time constant. |
| What is the meaning of the term " Time constant of an RL circuit" the time required for the? | Current in the circuit to build up to 63.2% of the maximum Value. |
| After two time constants, the capacitor in a RC circuit is charge to what percent of the supply voltage? | 86.5% |
| After two time constants, the capacitor in a RC circuit is discharged to what % of the starting voltage? | 13.5% |
| What is the time constant of a circuit 220-micro farad capacitors and two 1-mega ohm resistors in parallel? | 220 seconds |
| What is the time constant of a circuit having two 100-micro farad capacitors and two 470-K ohm resistors all in series? | 47 seconds |
| What is the time constant of a circuit having a 100- micro farad capacitor and a 470- Kilo ohm resistor in series? | 47 seconds |
| What is the time constant of a circuit having a 220-micro farad capacitor and a 1-mega ohm resistor in parallel? | 220 seconds |
| What is the time constant of a circuit having two 100-micro farad capacitors and two 470-Kilo ohm resistors all in parallel? | 47 |
| What is the time constant of a circuit having 220-micro farad capacitors and two 1-mega ohm resistors all in series? | 220 seconds |
| What is the impedance of a network composed of a 0.1 microhenry inductor in series with a 20-ohm resistor, at 30 MHz? Specify answer in rectangular coordinates. | 20 +j19 |
| What is the impedance of a network composed of a 0.1-microhenry inductor in series with a 30-ohm resistor, at 5 MHz? | 30 +j3 |
| What is the impedance of a network composed of a 10-microhenry inductor in a series with a 40-ohm resistor at 500 MHz? | 40 +j31400 |
| What is the impedance of a network composed of a 1.0-millihenry inductor in series with a 200-ohm resistor at 30 kHz? | 200 +j188 |
| What is the impedance of a network composed of a 0.01-microfarad capacitor in parallel with a 300-ohm resistor at 50 kHz? | 159 -j150 |
| What is the impedance of a network composed of a 0.001-microfarad capacitor in series with a 400-ohm resistor, at 500 kHz? | 400- j318 |
| What is the impedance of a network composed of a 100-picofarad capacitor in parallel with a 4000-ohm resistor, at 500kHz? Specify in polar coordinates. | 2490 ohms -51.5 degrees |
| What is the impedance of a network composed of a 100-ohm reactance inductor in series with a 100-ohm resistor? | 141 ohms 45 degrees |
| What is the impedance of a network composed of a 400-ohm reactance capacitor in series with a 300-ohm resistor? | 500 ohms -53.1 degrees |
| What is the impedance of a network composed of 300-ohm reactance capacitor, a 600-ohm reactance inductor, and a 400-ohm resistor, all in series? | 500 ohms 37 degrees |
| what is the impedance of a network composed of a 400-ohm reactance inductor in parallel with a 300-ohm resistor? | 240 ohms 36.9 degrees |
| What is the magnitude of the impedance of a series AC circuit having a resistance of 6 ohms, an inductive reactance of 17 ohms, and zero capacitive reactance? | 18 ohms |
| A 1- watt, 10 volt Zener diode with the characteristics Imin= 5mA; Imax=95mA; and Z= 8 ohms, is to be used as part of a voltage regulator in a 20-V ps. ~ what size current-limiting resistor would be used to set its bias to the midpoint operating range? | 200 ohms ref pg.99 |
| Given a power supply with a no load voltage of 12 volts and full load voltage of 10 volts, what is the % of voltage regulation? | 20% |
| What turns ratio does a transformer need in order to match a source impedance of 500 ohms to a load of 10 ohms? | 7.1 to 1 |
Created by:
CMcLeod92