Indicate the false statement
A. The noise generated in a resistance or the resistive component of any impedance is
random.
B. Random noise power is proportional to the bandwidth over which is measured
C. A random voltage across the resistor does not exist
D. All formula referring to random noise are applicable only to the value of such noise.

1 Answer

Answer :

C. A random voltage across the resistor does not exist

Related questions

Description : The square of the thermal noise voltage generated by a resistor is proportional to A. its resistance B. its temperature C. the bandwidth over which it is measured D. All of the above

Last Answer : D. All of the above

Description : Indicate the false statement. Noise figure is defined as A. the ratio of the S/N power supplied at the input terminal of a receiver or amplifier to the S/N power supplied to the output or ... under test, both working at the same temperature over the same bandwidth and fed from the same source

Last Answer : C. an unwanted form of energy tending to interfere with the proper and easy reception and reproduction of wanted signals

Description : Indicate the false statement. A. HF mixer are generally noisier than HF amplifiers. B. Impulse noise voltage is dependent on bandwidth C. Thermal noise is independent of the frequency at which is measured. D. Industrial noise is usually of the impulse type.

Last Answer : B. Impulse noise voltage is dependent on bandwidth

Description : At 17˚ C, the noise voltage generated by 5kΩ resistor, operating over a bandwidth of 20KHz is A. 1.3 nV B. 1.3 µV C. 1.3 pV D. 1.3 mV

Last Answer : B. 1.3 µV

Description : What is the noise voltage across a 300Ω input resistance to a TV set with a 6MHz bandwidth and temperature of 30˚C? A. 2.3 µV B. 3.8µV C. 5.5µV D. 5.4µV

Last Answer : C. 5.5µV

Description : Calculate the noise figure of the receiver whose RF amplifier has an input resistance of 1000Ω and an equivalent shot-noise resistance of 2000Ω, a gain of 25 and load resistance of 125 kΩ. Given that the bandwidth is 1. ... to an antenna with an impedance of 75Ω. A. 30.3 B. 3.03 C. 303 D. .303

Last Answer : A. 30.3

Description : The value of the resistor creating thermal noise is doubled. The noise power generated is therefore. A. halved B. quadrupled C. doubled D. unchanged

Last Answer : D. unchanged

Description : The presence of standing waves on a transmission line is the result of A. a high level of attenuation on the line. B. terminating the line by a resistive load equal in value to the surge impedance ... input power to below its critical level. D. an impedance mismatch between the load and the line.

Last Answer : D. an impedance mismatch between the load and the line.

Description : Transmission lines when connected to antenna have A. capacitive load B. resistive load whose resistance is less than characteristics impedance C. resistive load at the resonant frequency D. resistive load whose resistance is greater than the characteristic impedance of the line

Last Answer : C. resistive load at the resonant frequency

Description : The noise output of a resistor is amplified by a noiseless amplifier having a gain of 60 and a bandwidth of 20 kHz. A meter connected at the output of the amplifier reads 1mV RMS. If the bandwidth of the amplifier is reduced to ... does the meter read now? A. 0.5 mV B. 0.5 µV C. 5.0 mV D. 5.0 µV

Last Answer : A. 0.5 mV

Description : The first stage of a two-stage amplifier has a voltage gain of 10, a 600 Ω input resistor, a 1600Ω equivalent noise resistance and 27kΩ output resistor. For the second stage, these values are 25, 81kΩ, 19kΩ, and 1MΩ, ... this two stage amplifier. A. 2,518 kΩ B. 2,518 Ω C. 251.8 Ω D. 12,518 Ω

Last Answer : B. 2,518 Ω

Description : The ratio of the level of the modulated output of a transmitter under conditions of standard test modulation to the level of the demodulated output with no modulation applied both measured with the ... . Reference audio output B. None of these C. Audio frequency response D. Residual noise level

Last Answer : D. Residual noise level

Description : ___________ is device that measures the internal open circuit voltage of an equivalent noise generator having an impedance of 600Ω and delivering noise power to a 600 Ω load. A. Psophometer B. Barometer C. Reflectometer D. Voltmeter

Last Answer : A. Psophometer

Description : Indicate the false statement. A. Industrial noise is usually of the impulse type B. Static is caused by lightning discharges in thunderstorms and other natural electric disturbances occurring in the ... another source of man-made noise D. Flourescent lights are another source of man-made noise

Last Answer : C. Distant stars are another source of man-made noise

Description : An amplifier operating over the frequency range of 455 to 460 kHz has a 200 kΩ input resistor. What is the RMS noise voltage at the input to this amplifier if the ambient temperature is 17˚C ? A. 40 µV B. 4.0 µV C. 400 µV

Last Answer : B. 4.0 µV

Description : Not a reason for the use of an antenna coupler. A. To make the antenna look resistive B. To provide the output amplifier with the correct load impedance C. To discriminate against harmonics D. To prevent re-radiation of the local oscillator

Last Answer : D. To prevent re-radiation of the local oscillator

Description : Two resistors, 20kΩ, and 50kΩ are at ambient temperature. Calculate for a bandwidth equal to 100kHz, the thermal noise voltage for the two resistors connected in parallel. A. 0.4782µV B. 4278 µV C. 4.78 µV D. 47.8 µV

Last Answer : C. 4.78 µV

Description : What is meant by referring to electromagnetic waves as having circular polarization? A. The electric field is bent into a circular shape. B. The electric field rotates C. The electromagnetic wave continues to circle the earth D. The electromagnetic wave has been generated by a quad antenna

Last Answer : B. The electric field rotates

Description : An RG-11/U foam coaxial cable has a maximum voltage standing wave of 52 V and a minimum voltage of 17 V. Find the value of the resistive load. A. 24.59Ω B. Either A or C C. 228.75Ω D. Neither A nor C

Last Answer : B. Either A or C

Description : Indicate the false statement about the resistance of a wire – (1) it depends on material of wire (2) it is directly proportional to the length of wire (3) it is directly proportional to the area of crosssection of wire (4) resistance of metallic wire increases with increase in temperature

Last Answer : (3) it is directly proportional to the area of cross-section of wire Explanation: The property of conductor due to which it opposes the flow of current through it is called Resistance. It is ... potential difference across its ends to the current flowing through it The SI unit of resistance is ohm.

Description : Indicate the false statement about the resistance of a wire (1) it depends on material of wire (2) it is directly proportional to the length of wire (3) it is directly proportional to the area of cross-section of wire (4) resistance of metallic wire increases with increase in temperature

Last Answer :  it is directly proportional to the area of cross-section of wire

Description : Which of the following is not a way of minimizing if not eliminating noise? A. Use redundancy B. Increase transmitted power C. Reduce signaling rate D. Increase channel bandwidth

Last Answer : D. Increase channel bandwidth

Description : The total noise power present in a 1-Hz bandwidth . A. Noise density B. Noise figure C. Noise limit D. Noise intensity

Last Answer : A. Noise density

Description : What bandwidth is needed to support a capacity of 128 kbps when the signal power to noise power ratio in decibels is 100? A. 19224 Hz B. 3853 Hz C. 19244 Hz D. 3583 Hz

Last Answer : B. 3853 Hz

Description : What kind of effect is referred to a varying light producing a varying voltage output of a detector? A. Current effect B. Voltage effect C. Resistive effect D. Photovoltaic effect

Last Answer : D. Photovoltaic effect

Description : When troubleshooting most electronic circuits, 'loading effect' can be minimized by using a voltmeter with a/an ___________________. A. input impedance much greater than the impedance across which the voltage ... sensitivity of less than 1000 ohms/volt D. sensitivity of more than 1000 volts/ohm

Last Answer : Answer: A

Description : If current of 20 mA is passing through op-amp and voltage drop across series resistor is 10 V then value of resistance is A. 500Ω B. 400Ω C. 300Ω D. 200Ω

Last Answer : 500Ω

Description : What voltage would be measured across the 45 ohm resistor?

Last Answer : Not enough information. But if you know the current, you can useOhm's Law (just multiply the resistance times the current).

Description : Four amperes of current are measured through a 24 ohms resistor connected across a voltage source. How much voltage does the source produce? A.960 V B.9.6 V C.96 V D.8 V

Last Answer : Four amperes of current are measured through a 24 ohms resistor connected across a voltage source. How much voltage does the source produce? A.960 V B.9.6 V C.96 V D.8 V

Description : Which preamplifier design (high-impedance or transimpedance) provides improvements in bandwidth and greater dynamic range with some degradation in sensitivity from an increase in noise?

Last Answer : Transimpedance.

Description : Noise can be reduced by A. widening the bandwidth B. narrowing the bandwidth C. increasing temperature D. increasing transistor current levels

Last Answer : B. narrowing the bandwidth

Description : Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission. A. Radiation B. Noise C. Out of the band D. Interference

Last Answer : C. Out of the band

Description : Which does not effect noise in a channel? A. None of these B. Bandwidth C. Temperature D. Quantizing level

Last Answer : D. Quantizing level

Description : Noise from random acoustic or electric noise that has equal energy per cycle over a specified total frequency band. A. Gaussian noise B. Whiter noise C. Thermal noise D. All of the above

Last Answer : D. All of the above

Description : Noise from random acoustic or electric noise that has equal per cycle over a specified total frequency band. A. Thermal noise B. White noise C. Gaussian noise D. All of these

Last Answer : D. All of these

Description : Calculated the noise figure of the amplifier whose Req equals 2518Ω (RT=600Ω) if its driven by a generator whose output impedance is 50Ω. A. 39.4 B. 3.94 C. 394 D. 0.394

Last Answer : A. 39.4

Description : A transmission line of unknown impedance is terminated with two different resistances, and an SWR is measured each time. With a 75 Ω termination, the SWR measures 1.5. With a 300 Ω termination, it measures 2.67. What is the impedance of the line? A. 100 Ω B. 212 Ω C. 300 Ω D. 112 Ω

Last Answer : D. 112 Ω

Description : Characteristics impedance of a transmission line is the impedance measured at the ___________ when its length is infinite. A. input B. shorted end of the line C. output D. midsection

Last Answer : A. input

Last Answer : The noise generated by a resistor depends upon its operating temperature.

Description : One of the following is not a useful quantity for comparing the noise performance receivers. A. Input noise voltage B. Equivalent noise resistance C. Noise temperature D. Noise figure.

Last Answer : A. Input noise voltage

Description : What does the noise weighting curve shows? A. Noise signals measured with a 144 handset B. Power levels of noise found in carrier systems C. The interfering effect of other frequencies in a voice ... a reference frequency of one kilohertz D. Interfering effects of signals compared with a 3-kHz tone

Last Answer : C. The interfering effect of other frequencies in a voice channel compared with a reference frequency of one kilohertz

Description : Where is the noise generated that primarily determines the signal-to-noise ratio in a VHF (150MHz) marine-band receiver? A. Man-made noise B. In the atmosphere C. In the receiver front end D. In the ionosphere

Last Answer : C. In the receiver front end

Description : Where is the noise generated that primarily determines the signal-to-noise ratio in a VHF (150 MHz) marine-band receiver? A. In the ionosphere B. In the receiver rear end C. In the receiver front end D. In the atmosphere

Last Answer : C. In the receiver front end

Description : Which of the electrical properties listed will always be the same for each component in a parallel circuit? A. Impedance B. Current C. Resistance D. Voltage

Last Answer : Answer: D

Description : What component in the telephone set has the primary function of interfacing the handset to the local loop? A. Varistor B. Induction coil C. Resistor D. Capacitor

Last Answer : B. Induction coil

Description : What component in the telephone set has the primary function of interfacing the handset to the local loop? A. Varistor B. Induction coil C. Resistor D. Capacitor

Last Answer : B. Induction coil

Description : Which of the following methods cannot be used to increase the bandwidth for cascaded RF amplifier stages? A) Wave traps in each stage B) Stagger tuning C) A shunt damping resistor across each tuned circuit D) Doubled tuned transformers with tighter coupling

Last Answer : A) Wave traps in each stage

Description : What is meant by the term radiation resistance for an antenna? A. The resistance in the trap coils to received signal B. An equivalent resistance that would dissipate the same amount of power as ... antenna C. The specific impedance of the antenna D. Losses in the antenna elements and feed line

Last Answer : B. An equivalent resistance that would dissipate the same amount of power as that radiated from an antenna

Description : Most three-phase induction motors used for driving engine room auxiliaries are started by _____________. A. resistor starters B. across-the-line starters C. impedance starters D. reactor starters

Last Answer : Answer: B