Calculate the reverberation time of a living room 8 ft high, 13 ft wide and 20 ft long. The
total absorption of the building structure inside the room is 180.7 sabines with four persons
present in the room.
A. 0.5 ms
B. 0.05 s
C. 0.5 s
D. 5 ms

1 Answer

Answer :

C. 0.5 s

Related questions

Description : The reverberation time of a 184.2 cubic meters broadcast studio is 0.84 sec. Find the absorption effect of the materials used in metric sabines. A. 35.3 B. 10.96 C. 379.8 D. 109.6

Last Answer : A. 35.3

Description : Determine the additional absorption (sabines) contributed by 10 persons in a room A. 47 B. 4.7 C. 0.47 D. 470

Last Answer : A. 47

Description : What is the optimum reverberation time at 500 to 1000 Hz of an auditorium? A. 0.9 to 1.1 s B. 1.4 to 1.6 s C. 1.5 to 1.6 s D. 1.6 to 1.8 s

Last Answer : D. 1.6 to 1.8 s

Description : _______ is the transmission of sound from one room to an adjacent room thru common walls, floors or ceilings. A. Reverberation B. Refraction C. Flanking transmission D. Reflection

Last Answer : C. Flanking transmission

Description : What is the optimum reverberation time at 500 Hz for a cinema? A. 0.8 – 1.2 sec. B. 0.9 – 1.3 sec. C. 0.6 – 0.8 sec. D. 0.45 – 0.55 sec.

Last Answer : A. 0.8 – 1.2 sec.

Description : A ground station is operating to a geostationary satellite at a 5° angle of elevation. Calculate the round-trip time between ground station and satellite. A. 275 s B. 275 ms C. 137.5 s D. 137.5 ms

Last Answer : B. 275 ms

Description : Find the equivalent inductance per foot of the above cable? A. 13.5 nF/ft B. 13.5 pF/ft C. 116.8 nH/ft D. 116.8 pF/ft

Last Answer : C. 116.8 nH/ft

Description : In acoustics, _____ is the apparent change in frequency or pitch when a sound source moves either toward or away from a listener. A. flanking B. reverberation C. Doppler effect D. echo

Last Answer : C. Doppler effect

Description : Which of the following is NOT an acoustical defect to be avoided in acoustical designs? A. Reverberation B. Flutter echo C. Distortion D. Sound concentration

Last Answer : A. Reverberation

Description : What do you call the perceptible sound repetition? A. Reverberation B. Echo C. Reflection D. Masking

Last Answer : B. Echo

Description : The frequency of a wave travelling at a speed of 500 ms-1 is 25 Hz. Its time period will be ______. (i) 20 s (ii) 0.05 s (iii) 25 s (iv) 0.04 s

Last Answer : (iv) 0.04 s

Description : Has your opinion of someone ever been totally changed 180 degrees after you saw the inside of their personal living space (i.e. their house being a total mess)?

Last Answer : answer:No, but I did decide on the spot that I would never eat food that came from her house. To spare you the gory details, let’s just say – nasty.

Description : What is the delay time for satellite transmissions from earth transmitter to earth receiver? A. 0.5 s B. 1s C. 5 ms D. 0.25 s

Last Answer : A. 0.5 s

Description : What is the delay time for satellite transmission from earth transmitter to earth receiver? A. 0.5 s B. 1.0 s C. 5 ms D. 0.25 ms

Last Answer : A. 0.5 s

Description : The noise from an airplane engine 100 ft from an observer is found to have an intensity of 45dB. What will be the intensity when the plane flies overhead at an altitude of 1 mi? A. 10.5 dB B. 34.5 dB C. 35 dB D. 20.5 dB

Last Answer : A. 10.5 dB

Description : In acoustics, if the volume of the room is 200 m3 then at what frequency the coefficient of absorption is measured? A. 120 kHz B. 120 Hz C. 100 Hz D. 150 Hz

Last Answer : B. 120 Hz

Description : A T-section beam having flange 180mm wide and 20 mm thick and web 150 mm long and 20 mm thick carries a udl of 80 kN/m over an effective span of 8 m. Calculate the maximum bending stress.

Last Answer : Solution :

Description : Calorific value of proteins in a living person is less than that in a bomb calorimeter because (A) Digestion and absorption of proteins is less than 100% (B) Respiratory quotient of proteins ... Specific dynamic action of proteins is high (D) Proteins are not completely oxidized in living persons

Last Answer : Answer : D

Description : What absorber in which efficient absorption is only possible over a very narrow band approaching 1.0 (total absorption)? A. Porous material B. Helmholtz resonator C. Panel Absorber D. Membrane absorber

Last Answer : B. Helmholtz resonator

Description : What is the physical length of the above transmission line at 3/8λ long? A.0.82 m B. 0.82 ft C. 0.82 in D. 0.82 cm

Last Answer : B. 0.82 ft

Description : The total propagation delay time from transmission to reception of signals from a ground transmitter to ground receiver with angle of elevation at 10 degrees respectively is A. 273 ms B. 239 ms C. 275 ms D. 260 ms

Last Answer : A. 273 ms

Description : A radio signal moves from air to glass. The angle of incidence is 20°. Calculate the angle of refraction. The relative permittivity of the glass is 7.8. A. 7.8° B. 5.04° C. 6.04° D. 7.04°

Last Answer : D. 7.04°

Description : Calculate damping ratio if mass = 200Kg, ω = 20rad/s and damping coefficient = 800 N/m/s A. 0.03 B. 0.04 C. 0.05 D. 0.06

Last Answer : A. 0.03

Description : Calculate damping ratio from the following data: mass = 200Kg ω = 20rad/s damping coefficient = 1000 N/m/s a) 0.03 b) 0.04 c) 0.05 d) 0.06

Last Answer : b) 0.04

Description : Calculate damping ratio from the following data: mass = 200Kg ω = 20rad/s damping coefficient = 800 N/m/s a) 0.03 b) 0.04 c) 0.05 d) 0.06

Last Answer : a) 0.03

Description : Four persons rented a grassland. P grazed 48 goats for 3 months, Q grazed 20 goats for 5 months, R grazed 70 goats for 4 months and S grazed 42 goats for 3 months. If p’s share of rent is Rs.1420. Find the total rent of the field? A) 6410 B) 6200 C) 6400 D) 6300

Last Answer : Answer: A) Ratio of shares P,Q, R, S = 48*3 : 20 *5 : 70*4 :42*3 = 144 : 100: 280 : 126 = 72:50:140:63 Let total rent be Rs x Then P’s share = Rs. 72x/325 72x /325 = 1420 X = Rs.6410

Description : In the above problem, what is the new velocity of sound assuming dry air medium? A. 343 ft/s B. 3430 m/s C. 343 m/s D. 342 m/s

Last Answer : C. 343 m/s

Description : If temperature change is 19°C, what amount of change to sound velocity is possible? A. 11.53 ft/s B. 11.53 m/s C. 19.304 ft/s D. 19.304 m/s

Last Answer : B. 11.53 m/s

Description : At one atmospheric pressure, what is the approximate speed of sound in steel? A. 5150 m/s B. 5150 ft/s C. 4990 m/s D. 4990 ft/s

Last Answer : A. 5150 m/s

Description : The speech coding rate in D-AMPS is ____. A. 8 kbps B. 13 kbps C. 15 kbps D. 20 kbps

Last Answer : A. 8 kbps

Description : In GSM cellular system, the speech coding rate is ____. A. 13 kbps B. 8 kbps C. 15 kbps D. 20 kbps

Last Answer : A. 13 kbps

Description : In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raffinate ... phase is (in Kg) (A) 6.89 (B) 8.89 (C) 10 (D) 8.25

Last Answer : (B) 8.89

Description : What is the relationship in degrees of the electrostatic and electromagnetic fields of an antenna? A. 0 degree B. 45 degrees C. 90 degrees D. 180 degrees

Last Answer : C. 90 degrees

Description : A rectangular room is 6m long, 5m wide and 4m high. What is the total volume of the room in cubic meters? A. 24 B. 30 C. 120 D. 240

Last Answer : ANSWER: C

Description : A rectangular room is 6m long, 5m wide and 4m high. What is the total volume of the room in cubic meters? A. 24 B. 30 C. 120 63 D. 240

Last Answer : ANSWER: C

Description : The major role of minor elements inside living organisms is to act as (a) co-factors of enzymes (b) building blocks of important amino acids (c) constituent of hormones (d) binder of cell structure.

Last Answer : (a) co-factors of enzymes

Description :  In a birthday party, every person shakes hand with every other person. If there was a total of 66 handshakes in the party, how many persons were present in the party? A) 9 B) 8 C) 7 D) 12

Last Answer : Answer: D)  Assume that in a party every person shakes hand with every other person  Number of hand shake = 66  Total number of hand shake is given by nC2  Let n = the total number of persons ... cannot take negative value of n  So, n = 12  Therefore number of persons in the party = 12

Description : What is the velocity factor of coaxial cable with a characteristic impedance of 50Ω and capacitance of 30pF/ft and inductance of 75 nH/ft? A. 0.58 B.0.68 C. 0.98 D. 0.81

Last Answer : B.0.68

Description : If the operating frequency is 450 MHz what length of a pair of conductors is considered to be a transmission line? A. 2.19 ft B. 2.19 m C. 0.219 ft D. 0.219 m

Last Answer : C. 0.219 ft

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 : What is the maximum line-of-sight distance between a paging antenna 250 ft high and a pager receiver 3.5ft of the ground? A. 25 km B.25mi C. 70.73 km D. 70.73 mi

Last Answer : B.25mi

Description : If a 99.79 kg man jumps from the top of a 176.8 meter tall building how long does it take for his body to decelerate to 0 ms once first contact with the ground is made?

Last Answer : It depends upon how much the ground deforms once the first bit of his body hits the ground, and how much his body deforms once the first bit of his body has hit the ground. The former is likely to be ... his body). It will be any time greater than 0 seconds, the the amount of time depends as above.

Description : Determine the terrain sensitivity loss for a 4-GHz carrier that is propagating over a very dry, mountainous area. A. -1.25 dB B. -3.05 dB C. -2.01 dB D. -5.01 dB

Last Answer : A. -1.25 dB

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 : Using the data in question 7, calculate the 95% confidence interval for the mean ACT score based on the t-distribution. a. -∞ to 23.05 b. -∞ to 23.15 c. 18.07 to 23.63 d. 18.22 to 23.48

Last Answer : c. 18.07 to 23.63

Description : A 1000W carrier is amplitude modulated to a depth of 85%. Calculate the total power of the modulated wave? A. 1361.25 W B. 680.62 W C. 1425 W D. 712.5 W

Last Answer : A. 1361.25 W

Description : Oxygen molecule absorption peaks to electromagnetic wave are at what wavelengths? A. 1.35 cm and 1.7 mm B. 5 mm and 2.5 mm C. 5 cm and 2.5 cm D. 1.35 mm and 1.7 μm

Last Answer : B. 5 mm and 2.5 mm

Description : Which of the following wavelengths where absorption of electromagnetic waves becomes peak due to vibrational resonances in the water vapor molecule? A. 1.35 cm and 1.7 mm B. 1.5 mm and 5 mm C. 1.35 dm and 1.7 cm D. 1.5 cm and 5mm

Last Answer : A. 1.35 cm and 1.7 mm

Description : Oxygen molecule absorption peaks to electromagnetic wave are at what wavelengths? A. 1.35 mm and 1.7 μm B. 1.35 cm and 1.7 mm C. 5 cm and 2.5 cm D. 5 mm and 2.5 mm

Last Answer : D. 5 mm and 2.5 mm