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 : 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 : 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 : 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 pitch of sound is measured by its (a) Intensity (b) Waveform (c) Frequency (d) Loudness
Last Answer : Ans:(c)
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 : 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 : What is the phase coefficient in radians per unit length of a transmission line at the frequency of 10 MHz if the velocity of propagation is 2.5x108 m/s? A. 0.25 B. 2.5 C. 0.35 D. 3.5
Last Answer : A. 0.25
Description : Coherence of laser light is important for _________ ∙ a. Light propagation ∙ b. Getting laser light to pass through air ∙ c. Drilling holes ∙ d. Holography
Last Answer : d. Holography
Description : Which of the following contributes to the broadening of laser emission bandwidth? a. Doppler shift of moving atoms and molecules b. Amplification within the laser medium c. Coherence of the laser light d. Optical pumping of the laser transition
Last Answer : a. Doppler shift of moving atoms and molecules
Description : While propagating through homogeneous, isotropic media, (A) Directions of both the fields are orthogonal (B) Both the fields are at right angles to the direction of propagation (C) Both (a) and (b) (D) Neither (a) nor (b)
Last Answer : Answer: Option C
Description : Electromagneticwaves are refractedwhen they a. pass into a medium of different dielectric constant b. are polarized at right angles to the direction of propagation c. encounter a perfectly conducting plane d. pass through a small slot in a conducting plane
Last Answer : a. pass into a medium of different dielectric constant
Description : Sound energy passing per second through a unit area held perpendicular is called - (1) Intensity (2) Frequency (3) Amplitude (4) Quality
Last Answer : (1) Intensity Explanation: Sound energy passes through a unit area held perpendicular to the direction of propagation of sound waves is called intensity of sound.
Description : What device measures the angle between two radio frequencies and also the direction of propagation of a wave? A. Densimeter B. Absorption wavemeter C. Goniometer D. Ergometer
Last Answer : C. Goniometer
Description : An electromagnetic wave is ________ polarized when the electric field lies wholly in one plane containing the direction of propagation. A. Horizontally B. Linearly C. Circularly D. Vertically
Last Answer : B. Linearly
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 : 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 : 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 : 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 apparent loudness of 80 dB? A. Moderate B. Very loud C. Loud D. Deafening
Last Answer : B. Very loud
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 : At what loudness level do pitch (in mels) and frequency (in Hz) are numerically equal? A. 0 dB B. 20 dB C. 60 dB D. 40 dB
Last Answer : D. 40 dB
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
Description : Which of the following is the unit of perceived loudness of sound? (1) Decibel (2) Sone (3) Hertz (4) Phon
Last Answer : (2) Sone Explanation: Loudness is a subjective characteristic of a sound (as opposed to the sound-pressure level in decibels, which is objective and directly measurable). Perceived loudness of sound ... on sound pressure level, the frequency spectrum, and the time behavior of the sound in question.
Description : Which of the following is the unit of perceived loudness of sound ? (1) Decibel (2) Sone (3) Hertz (4) Phon
Last Answer : Sone
Description : In electromagnetic waves, the electric field will be perpendicular to which of the following? a) Magnetic field intensity b) Wave propagation c) Both H and wave direction d) It propagates independently
Last Answer : c) Both H and wave direction
Description : What sound intensity corresponds to a sound-intensity level of 50dB? A. 1 x 10-6W/m2 B. 1 x 10-7W/m2 C. 1 x 10-8W/m2 D.1 x 10-5W/m2
Last Answer : B. 1 x 10-7W/m2
Description : For the safety and comfort of factory workers, the sound-intensity level in a certain factory must remain below 85 dB. What is the maximum sound intensity allowed in this factory? A. 3.2 x 10-4 W/m2 B. 3.2 x 10-6 W/m2 C. 3.2 x 10-10 W/m2 D. 3.2 x 10-3 W/m2
Last Answer : A. 3.2 x 10-4 W/m2
Description : A choir consisting of 36 individuals all of whom can sing with the same intensity. A soloist sings a certain passage and then is joined by the remainder of the choir members for a repeat of the passage. What is the ... sound intensity level in the two cases? A. 3 dB B. 6 dB C. 36 dB D. 15.6dB
Last Answer : D. 15.6dB
Description : ECE Board Exam April 1997 Sound intensity is given as A. df/dP B. dE/dp C. dA/dP D. dP/dA
Last Answer : D. dP/dA
Description : Sound intensity level is ________. A. 10 log I/I(ref) B. 10 log I(ref)/I C. 30 log I/I(ref) D. 20 log I/I(ref)
Last Answer : A. 10 log I/I(ref)
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 : Cable attenuation is usually expressed in terms of a. Loss per foot b. dB/km c. intensity per mile d. voltage drop per inch
Last Answer : b. dB/km
Description : It is an energy flux, equal to the rate of energy flow per unit area per unit time across some surface. a. Irradiance b. Radiant Intensity c. Luminosity d. Brightness
Last Answer : Luminosity
Description : A dielectric waveguide for the propagation of electromagnetic energy at light frequencies a. Stripline b. Microstrip c. Laser beam d. Fiber optics
Last Answer : d. Fiber optics
Description : A train moving at 60 kilometers per hour is struck by a bullet moving 1000 m/sec at right angles to the train. The direction with which the bullet appears to strike the train would be a.75? b.60? c.22 d.30? e.45?
Last Answer : e. 45?
Description : ______ is an antenna array which is highly directional at right angles to the plane of the array? A. Broadside array B. End-fire array C. Turnstile array D. Log-periodic array
Last Answer : A. Broadside array
Description : A simple half-wavelength antenna radiates the strongest signal A. at 45 degrees to its axis B. parallel to its axis C. at right angles to its axis D. at 60 degrees to its axis
Last Answer : C. at right angles to its axis
Description : What are electromagnetic waves? A. Alternating currents in the core of an electromagnet B. A wave consisting of two electric fields at right angles to each other C. A wave consisting of an electric field ... to each other D. A wave consisting of two magnetic fields at right angles to each other
Last Answer : C. A wave consisting of an electric field and a magnetic field at right angles to each other
Description : What are electromagnetic waves? A. A wave consisting of two magnetic fields at right angles to each other B. A wave consisting of an electric field and a magnetic field at right angles to each ... core of an electromagnet D. A wave consisting of two electric fields at right angles to each other
Last Answer : B. A wave consisting of an electric field and a magnetic field at right angles to each other.
Description : Velocity of sound in air does not change with the change of – (1) Temperature of air (2) Pressure of air (3) Moisture content in air (4) Wind in the direction of propagation of sound
Last Answer : (2) Pressure of air Explanation: The speed of sound in an ideal gas is independent of frequency, but it weakly depends on frequency for all real physical situations. It is a function of the ... ideal gas. Sound speed is slightly dependent on pressure only because air is not quite an ideal gas.
Description : Velocity of sound in air does not change with the change of (1) Temperature of air (2) Pressure of air (3) Moisture content in air (4) Wind in the direction of propagation of sound
Last Answer : Pressure of air
Description : The loudness of a sound is the waves ?
Last Answer : apex-frequency
Description : The quality of sound depends upon its (a) Waveform (b) Frequency (c) Loudness (d) Pitch
Last Answer : Ans:(a)
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 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 : 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 : If viewed on an oscilloscope, the loudness of a sound wave would be associated with the wave's: w) frequency x) wavelength y) velocity z) amplitude
Last Answer : ANSWER: Z -- AMPLITUDE