Description : The agreed standard for measuring loudness is the loudness sensation produced by a 1000 Hz sine wave _____ dB above the listener’s threshold of hearing. A. 80 B. 50 C. 30 D. 40
Last Answer : D. 40
Description : For a loudness level between 110 and 120 dB, the maximum daily exposure limit is ____ minute (s). A. 1 B. 60 C. 20 D. 45
Last Answer : A. 1
Description : What is the typical loudness level of a watch ticking? A. 0 phon B. 40 phons C. 20 phons D. 60 phons
Last Answer : C. 20 phons
Description : What is affected by the distance between the listener and the source of the sound because the intensity varies inversely with the square of the distance? A. Volume B. Pitch C. Loudness D. Frequency
Last Answer : C. Loudness
Description : What loudness level in which permanent damage to hearing is possible? A. 120 dB B. 140 dB C. 130 dB D. 150 dB
Last Answer : D. 150 dB
Description : What is the required quality factor for an SSB filter with the following data: center frequency= 1 MHz, the desired attenuation level of the unwanted sideband= 80 dB and the separation between sidebands= 200 Hz? A. 1,250 B. 12,500 C. 125,000 D. 25,000
Last Answer : C. 125,000
Description : The sound intensity received from the nearby jet plane is 12.6 µW/m2 and that from another jet plane some distance away is 0.45 µW/m2 . Find the relative loudness of the two. A. 14.0 dB B. 14.5dB C. 12.5 D. 14.5
Last Answer : B. 14.5dB
Description : What is the apparent loudness of 80 dB? A. Moderate B. Very loud C. Loud D. Deafening
Last Answer : B. Very loud
Description : The loudness level increased from 40 to 56 phons. What is the increase in loudness sensation? A. 3 times B. 4.5 times C. 2 times D. 4 times
Last Answer : A. 3 times
Description : Part of a microwave link can be approximated by free space conditions. The antenna gain are each 40 dB, the frequency is 10 GHz, and the path length is 80 km. Calculate the receive power for a transmitted power of 10 W? A. 0.871 μW B. 871 μW C. 0.871 mW D. 871 nW
Last Answer : A. 0.871 μW
Description : What is the quantization signal-to-noise ratio if an 8-bit PCM code is used? A. 40 dB B. 50 dB C. 60 dB D. 65 dB
Last Answer : B. 50 dB
Description : The frequency-response specification of your tape recorder reads within +/ - 3 dB from 150 Hz to 150 kHz at 60 ips. What does this mean?
Last Answer : The recorder can record all frequencies between 150 Hz and 150 kHz at 60 ips without varying the output amplitude more than 3 dB.
Description : What is the gain, in dB of a helical antenna with diameter of λ/3, 10 turns at pitch of λ/4, used at 100 MHz? A. 16 B. 41.1 C. 31.4 D. 1.25
Last Answer : A. 16
Description : The quality of sound depends upon its (a) Waveform (b) Frequency (c) Loudness (d) Pitch
Last Answer : Ans:(a)
Description : The pitch of sound is measured by its (a) Intensity (b) Waveform (c) Frequency (d) Loudness
Last Answer : Ans:(c)
Description : Loudness of sound depends on – (1) Frequency (2) Wavelength (3) Amplitude (4) Pitch
Last Answer : (3) Amplitude Explanation: Loudness depends on the amplitude of the sound wave. The larger the amplitude the more energy the sound wave contains therefore the louder the sound. The pitch of a note depends on the frequency of the source of the sound.
Description : Which among the following determines the pitch of a sound? (1) Amplitude (2) Frequency (3) Loudness (4) Wavelength
Last Answer : (2) Frequency Explanation: The pitch of a sound is determined by the frequency of vibration of the sound waves So higher the frequency the higher is the pitch.
Description : The pitch of the sound is measured by its: (1) Intensity (2) waveform (3) Frequency (4) Loudness
Last Answer : (3) Frequency Explanation: Pitch relates to the frequency, or how many times a second the particles vibrate. The distance between one wave and the next gives the wavelength. For sounds all travelling at the same speed, highfrequency (high-pitched) sounds have waves very close together.
Description : Higher the frequency greater will be ________. a)pitch b)loudness c)amplitude d)infrasound
Last Answer : a)pitch
Description : Loudness of sound depends on (1) Frequency (2) Wavelength (3) Amplitude (4) Pitch
Last Answer : Amplitude
Description : A reading of -50 dBm on the disturbing pair, and -80 on the disturbed pair equals _____ dB of crosstalk coupling. A. 20 B. 30 C. 60 D. 25
Last Answer : B. 30
Description : The international pitch A is equivalent to ___ Hz. A. 435 B. 440 C. 260 D. 255
Last Answer : A. 435
Description : The American concert pitch A is equivalent to which if the following frequencies? A. 440 Hz B. 435 Hz C. 260 Hz D. 255 Hz
Last Answer : A. 440 Hz
Description : What signal-to-noise ratio is required for satisfactory television reception? A. 10 dB B. 30 dB C. 40 dB D. 20 dB
Last Answer : C. 40 dB
Description : The signal to noise ratio that is required for a satisfactory television reception. A. 30 dB B. 40 dB C. 10 dB D. 20 dB
Last Answer : B. 40 dB
Description : The total space loss of transmission and reception for two ground stations with uplink frequency 8GHz and a downlink of 6 GHz with angle of elevations of 3˚ and 7˚ A respectively is A. 403 dB B. 100 dB C. 20 dB D. 215 dB
Last Answer : A. 403 dB
Description : What is typical loudness level of an acoustic guitar 1 foot away? A. 60dB B. 100dB C. 80dB D. 40dB
Last Answer : C. 80dB
Description : If the loudness level is 100 phons, what is this in sone unit? A. 100 B. 90 C. 106 D. 96
Last Answer : C. 106
Description : The frequency tolerance of an AM radio broadcast station A. 200 Hz B. 2000 Hz C. 20 Hz D. 2 Hz
Last Answer : C. 20 Hz
Description : A carrier signal has ______. A. Constant peak amplitude B. The information C. Frequency range 20-20000 Hz D. A varying amplitude
Last Answer : A. Constant peak amplitude
Description : You are measuring noise at a +3 dB level point, using the Lenkurt 601A, F1A weighting network, and a flat meter. The meter reading is -57dBm. This is ________dBa0. A. 20 B. 15 C. 25 D. 17
Last Answer : C. 25
Description : You are measuring noise in a voice channel at 7 dB test point level. The meter reads -56 dBm (FIA weighted). What is the reading in dBrnc? A. 20 B. 32 C. 35 D. 25
Last Answer : C. 35
Description : How does the gain of a parabolic dish type antenna change when the operating frequency is doubled? A. Gain does not change B. Gain is multiplied by 0.707 C. Gain increases 6 dB D. Gain increases 3 dB
Last Answer : C. Gain increases 6 dB
Description : What is the effective radiated power of a repeater with 120 watts transmitter power output, 5 dB feedline loss, 4 dB duplexer and circulator loss, and 6 dB antenna gain? A. 601 W B. 240 W C. 60 W D. 379 W
Last Answer : C. 60 W
Description : If you have available number of power amplifiers with a gain of 100 each, how many such amplifiers do you need to cascade to give an overall gain of 60 dB? A. 3 B. 4 C. 5 D. 2
Last Answer : A. 3
Description : The lowest frequency produced by an instrument. A. Harmonic B. Fundamental C. Midrange D. 0 Hz
Last Answer : B. Fundamental
Description : Three identical circuits having 10 dB signal noise-to-noise ratio each are connected in tandem with each other, what is the overall S/N? A. 5.23 dB B. 14.77dB C. 30 dB D. 40 dB
Last Answer : A. 5.23 dB
Description : What is the number of levels required in a PCM system with S/N ratio of 40 dB? A. 64 B. 128 C. 256 D. 512
Last Answer : B. 128
Description : ECE Board Exam March 1996 A car horn outdoors produces a sound intensity level of 90 dB at 10 ft away. At this distance, what is the sound power in watt? A. 12 W B. 0.12 W C. 0.012 W D. 1.2 W
Last Answer : C. 0.012 W
Description : The loudness of sound depends upon (1) Velocity (2) Pitch (3) Amplitude (4) Wavelength
Last Answer : (3) Amplitude Explanation: Loudness is the characteristic of a sound that is primarily a psychological correlate of physical strength (amplitude).
Description : Loudness of sound varies directly with vibrating body’s – (1) Intensity (2) Amplitude (3) Pitch (4) Quality
Last Answer : (2) Amplitude Explanation: Loudness of Sound: Loudness of sound depends on amplitude of vibration. Loudness of sound is directly proportional to square of amplitude of vibration.
Description : Which characteristic is this? We can distinguish between sound having same pitch and loudness. a)tone b)note c)pitch d)timbre
Last Answer : d)timbre
Description : Determine natural frequency of a system, which has equivalent spring stiffness of 43200 N/m and mass of 12 kg. A 40.22 rad/sec B 40 Hz C 60 Hz D 60 rad/sec
Last Answer : D 60 rad/sec
Description : Unit of frequency is ________________. A. Hz B. Horton C. dB D. Coulomb
Last Answer : Unit of frequency is Hz.
Description : What is the most commonly used intermediate frequency of radar receivers? A. 40 MHz B. 60 MHz C. 70 MHz D. 30 MHz
Last Answer : D. 30 MHz
Description : When the elevation angle of a geostationary satellite is 23˚ and the transmitting frequency is 3840 MHz, what is the free space loss in dB? A. 196 dB B. 200 dB C. 150 dB D. 100 dB
Last Answer : A. 196 dB
Description : What is the path attenuation between transmitter and receiver at a frequency of 1.2 Ghz and a distance of 11,000 mi? A. 119 dB B. 115dB C. 179dB D. 174dB
Last Answer : C. 179dB
Description : The sound energy per unit area at right angles to the propagation direction per unit time. A. Sound intensity B. Loudness C. Coherence D. Sound stress
Last Answer : A. Sound intensity
Description : ____________ is the average rate of transmission of sound energy in a given direction through a cross sectional area of 1 sq.m. at right angle to the direction. A. Sound pressure B. Sound intensity C. Pressure variation D. Loudness
Last Answer : B. Sound intensity
Description : ECE Board Exam March 1996 One type of pulse communications system uses pulse that appear as a group, and which vary in number according to the loudness of the voice. This type of ... A. pulse duration modulation B. pulse amplitude modulation C. pulse code modulation D. pulse position modulation
Last Answer : A. pulse duration modulation