Deck 12: Sound

Question 1

The speed of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the velocity of sound in air at a temperature of 30 $^{\circ}$ C?

A) 336 m/s
B) 338 m/s
C) 340 m/s
D) 342 m/s
E) 349 m/s

Answer 1

349 m/s

Question 2

The speed of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the velocity of sound in air at a temperature of -30 $^{\circ}$ C?

A) 308 m/s
B) 310 m/s
C) 312 m/s
D) 314 m/s
E) 316 m/s

Answer 2

312 m/s

Question 3

The speed of sound in water is 4.3 times the speed of sound in air.A whistle produces a sound wave in air with a frequency f₀.When this sound wave enters the water,its frequency becomes

A) 4.3 f_0.
B) f_0.
C) f₀/4.3.
D) not enough information

Answer 3

f_0.

Question 4

The velocity of bulk sound waves in brass is 2,813 m/s.If the density of brass is 8,470 kg/m³,then what is the bulk modulus of brass?

A) 5.30 $\times$ 10¹⁰ N/m²
B) 5.80 $\times$ 10¹⁰ N/m²
C) 6.10 $\times$ 10¹⁰ N/m²
D) 6.70 $\times$ 10¹⁰ N/m²
E) 7.50 $\times$ 10¹⁰ N/m²

Question 5

A sound wave radiates from a source in all directions.If the power of the sound source is 200 watts,then the intensity of the sound wave 100 m from the source is

A) 2.2 milliWatts/m².
B) 2.0 milliWatts/m².
C) 1.8 milliWatts/m².
D) 1.6 milliWatts/m².
E) 1.2 milliWatts/m².

Question 6

The intensity of a sound wave is directly proportional to

A) the frequency.
B) the amplitude.
C) the square of the amplitude.
D) the square of the speed of sound.
E) none of these answers are correct

Question 7

You see lightning flash followed 8.2 seconds later by the sound of thunder.The ambient air temperature is 12 $^{\circ}$ C.Approximately how far are you from the lightning?

A) 1.26 miles
B) 1.64 miles
C) 1.69 miles
D) 1.32 miles

Question 8

The bulk modulus of aluminum is 7.1 $\times$ 10¹⁰ N/m².If the density of aluminum is 2.7 $\times$ 10³ kg/m³,then what is the speed of sound in aluminum?

A) 4,500 m/s
B) 4,700 m/s
C) 4,900 m/s
D) 5,100 m/s
E) 5,500 m/s

Question 9

Compared to the speed of a 400 Hz sound,the speed of a 200 Hz sound through air is

A) twice as great.
B) the same.
C) one half as great.
D) none of these answers are correct

Question 10

The speed of sound in helium is 965 m/s.If the density of helium is 0.179 kg/m³,then what is the bulk modulus of helium?

A) 2.70 $\times$ 10⁵ N/m²
B) 2.40 $\times$ 10⁵ N/m²
C) 2.20 $\times$ 10⁵ N/m²
D) 1.67 $\times$ 10⁵ N/m²
E) 1.56 $\times$ 10⁵ N/m²

Question 11

Aluminum has a shear modulus of 2.4 $\times$ 10¹⁰ N/m² and a wave velocity for shear waves of 2,981 m/s.If the velocity of shear waves decreased by 10%,then what is the change in the shear modulus?

A) 35%
B) 30%
C) 25%
D) 20%
E) 15%

Question 12

The velocity of longitudinal waves in a long brass rod is 3,260 m/s.If the density of brass is 8,470 kg/m³,then what is the tensile modulus of brass?

A) 9.80 $\times$ 10¹⁰ N/m²
B) 9.00 $\times$ 10¹⁰ N/m²
C) 8.70 $\times$ 10¹⁰ N/m²
D) 8.50 $\times$ 10¹⁰ N/m²
E) 8.10 $\times$ 10¹⁰ N/m²

Question 13

The Young's modulus of aluminum is 6.90 $\times$ 10¹⁰ N/m².If the density of aluminum is 2,700 kg/m³,then what is the velocity of longitudinal waves along a thin aluminum rod?

A) 6,360 m/s
B) 6,020 m/s
C) 5,750 m/s
D) 5,060 m/s
E) 4,850 m/s

Question 14

Lead has a shear modulus of 5.40 $\times$ 10⁹ N/m² and a density of 11.3 $\times$ 10³ kg/m³.What is the velocity of shear waves in lead?

A) 691 m/s
B) 621 m/s
C) 575 m/s
D) 521 m/s
E) 487 m/s

Question 15

Brass has a shear modulus of 3.400 $\times$ 10⁹ N/m² and a density of 8.470 $\times$ 10³ kg/m³.What is the velocity of shear waves in brass?

A) 2,560 m/s
B) 2,239 m/s
C) 2,003 m/s
D) 1,981 m/s
E) 1,755 m/s

Question 16

A sound wave radiates from a source in all directions.If the power of the sound source is 200 watts,then the intensity level of the sound wave 100 m from the source is (in dB)

A) 98.5.
B) 92.0.
C) 91.5.
D) 89.6.
E) 88.3.

Question 17

The velocity of shear waves in a long brass rod is 2,033 m/s.If the density of brass is 8,470 kg/m³,then what is the shear modulus of brass?

A) 2.70 $\times$ 10¹⁰ N/m²
B) 3.10 $\times$ 10¹⁰ N/m²
C) 3.50 $\times$ 10¹⁰ N/m²
D) 4.10 $\times$ 10¹⁰ N/m²
E) 4.70 $\times$ 10¹⁰ N/m²

Question 18

Sound traveling in air at 23 $^{\circ}$ C enters a cold front where the air temperature is 2 $^{\circ}$ C.If the frequency of the sound is 1500 Hz,what is the difference in the wavelength between the cold air and the warm air?

A) 0.009 m
B) 0.019 m
C) 0.067 m
D) 0.058 m

Question 19

The bulk modulus of water is 0.210 $\times$ 10¹⁰ N/m² and the density is 1000 kg/m³.The velocity of sound in water is

A) 1,450 m/s.
B) 2,150 m/s.
C) 2,490 m/s.
D) 2,750 m/s.
E) 3,100 m/s.

Question 20

The speed of sound in air at 0 $^{\circ}$ C is 331 m/s.If the density of air is 1.29 kg/m³,then what is the bulk modulus of air?

A) 1.15 $\times$ 10⁵ N/m²
B) 1.41 $\times$ 10⁵ N/m²
C) 1.68 $\times$ 10⁵ N/m²
D) 2.03 $\times$ 10⁵ N/m²
E) 2.50 $\times$ 10⁵ N/m²

Question 21

A 60.0 cm long brass rod is suspended at the ends by long strings.The rod is struck at one end parallel to the rod and causes the rod to vibrate longitudinally with the ends free.(Y = 9.00 $\times$ 10¹⁰ N/m², S = 3.50 $\times$ 10¹⁰ N/m², B = 6.70 $\times$ 10¹⁰ N/m²,density = 8,470 kg/m³)The frequency of the vibration is

A) 3,790 Hz.
B) 3,540 Hz.
C) 3,120 Hz.
D) 2,720 Hz.
E) 2,140 Hz.

Question 22

A 60.0 cm long organ pipe is filled with air and is open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the wavelength of the fundamental mode?

A) 115 cm
B) 120 cm
C) 131 cm
D) 142 cm
E) 167 cm

Question 23

A sound wave radiates from a source in all directions.If the power of the sound source is 200 watts,then the intensity level of the sound wave 1000 m from the source is (in dB)

A) 62.8.
B) 66.0.
C) 68.5.
D) 70.5.
E) 72.0.

Question 24

The sound of a jet engine is given as 120 dB.What is the intensity of the jet sound wave?

A) 1.0 W/m²
B) 0.8 W/m²
C) 0.6 W/m²
D) 0.4 W/m²
E) 0.2 W/m²

Question 25

A 50.0 cm long organ pipe is filled with air and is open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the frequency of the second mode?

A) 662 Hz
B) 621 Hz
C) 587 Hz
D) 562 Hz
E) 550 Hz

Question 26

A 40.0 cm long organ pipe is filled with air and is open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.If the temperature of the air increases by 10 $^{\circ}$ C,then what is the frequency of the fundamental mode?

A) 367 Hz
B) 395 Hz
C) 401 Hz
D) 421 Hz
E) 480 Hz

Question 27

A 40.0 cm long organ pipe is filled with air and is open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.If the temperature of the air decreases by 10 $^{\circ}$ C,then what is the frequency of the fundamental mode?

A) 394 Hz
B) 406 Hz
C) 462 Hz
D) 506 Hz
E) 544 Hz

Question 28

The sound of a bird singing is given as 5 dB.What is the intensity of the sound of a bird singing?

A) 1.95 $\times$ 10^-12 W/m²
B) 2.04 $\times$ 10^-12 W/m²
C) 2.98 $\times$ 10^-12 W/m²
D) 3.16 $\times$ 10^-12 W/m²
E) 4.25 $\times$ 10^-12 W/m²

Question 29

A 3.0 m organ pipe is open at both ends and contains air.The velocity of sound in air is 331 m/s.What is the wavelength of the lowest frequency mode?

A) 1.5 m
B) 3.0 m
C) 6.0 m
D) 9.0 m
E) 12.0 m

Question 30

A 50 cm long organ pipe is filled with air and is open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the wavelength of the second mode?

A) 50 cm
B) 75 cm
C) 90 cm
D) 40 cm
E) 63 cm

Question 31

A sound wave in water has an intensity of 1.00 $\times$ 10^-3 Watts/m².The density of water is 1,000 kg/m³ and the velocity of sound in water is 1,482 m/s.The pressure amplitude of the sound wave is

A) 60.2 N/m².
B) 54.4 N/m².
C) 49.5 N/m².
D) 42.5 N/m².
E) 39.5 N/m².

Question 32

A 30.0 cm long brass rod is suspended at the ends by long strings.The rod is struck at one end parallel to the rod and causes the rod to vibrate longitudinally with the ends free.(Y = 9.00 $\times$ 10¹⁰ N/m², S = 3.50 $\times$ 10¹⁰ N/m², B = 6.70 $\times$ 10¹⁰ N/m²,density = 8,470 kg/m³)The frequency of the vibration is

A) 5,430 Hz.
B) 5,020 Hz.
C) 4,760 Hz.
D) 4,500 Hz.
E) 3,950 Hz.

Question 33

The sound of a band is rated as 60 dB at a distance of 10.0 m.What is the dB sound level of the band when one is 20.0 m from the band?

A) 56 dB
B) 54 dB
C) 52 dB
D) 50 dB
E) 48 dB

Question 34

The sound of a band is rated as 50 dB at a distance of 30.0 m.What is the dB sound level of the band when one is 10.0 m from the band?

A) 59.5 dB
B) 57.3 dB
C) 55.2 dB
D) 52.9 dB
E) 50.1 dB

Question 35

A 40.0 cm long organ pipe is filled with air and is open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the frequency of the fundamental mode?

A) 297 Hz
B) 314 Hz
C) 373 Hz
D) 385 Hz
E) 414 Hz

Question 36

A sound wave in helium has an intensity of 1.00 $\times$ 10^-3 Watts/m².The density of helium is 0.179 kg/m³ and the velocity of sound in helium is 965 m/s.The pressure amplitude of the sound wave is

A) 0.682 N/m².
B) 0.520 N/m².
C) 0.476 N/m².
D) 0.345 N/m².
E) 0.276 N/m².

Question 37

A 3.00 m organ pipe is open at both ends and contains air.The velocity of sound in air is 331 m/s.What is the frequency of the lowest frequency mode?

A) 39.5 Hz
B) 40.2 Hz
C) 43.1 Hz
D) 47.5 Hz
E) 55.2 Hz

Question 38

The three lowest resonate frequencies of a system are 50 Hz,150 Hz,and 250 Hz.The system could be

A) a tube of air closed at both ends.
B) a tube of air open at one end.
C) a tube of air open at both ends.
D) a vibrating string with fixed ends.

Question 39

A sound wave in air has an intensity of 1.00 $\times$ 10^-3 Watts/m².The density of air is 1.29 kg/m³ and the velocity of sound in air is 331 m/s.The pressure amplitude of the sound wave is

A) 0.740 N/m².
B) 0.821 N/m².
C) 0.850 N/m².
D) 0.924 N/m².
E) 0.980 N/m².

Question 40

A sound wave in brass has a displacement amplitude of 3.00 mm.The frequency of the sound wave 750 Hz and the velocity is 2,813 m/s.If the density of brass is 8.47 $\times$ 10³ kg/m³,then what is the pressure amplitude of the sound wave?

A) 5.38 $\times$ 10⁸ N/m²
B) 5.10 $\times$ 10⁸ N/m²
C) 4.70 $\times$ 10⁸ N/m²
D) 4.17 $\times$ 10⁸ N/m²
E) 3.37 $\times$ 10⁸ N/m²

Question 41

A string with a mass per length of 2.00 g/m is stretched between two points that are 0.400 m apart.The third mode frequency of the stretched string is 120 Hz higher than the fundamental mode frequency.What is the tension in the string?

A) 75.0 N
B) 96.0 N
C) 101 N
D) 120 N
E) 134 N

Question 42

A 30.0 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the frequency of the second mode?

A) 900 Hz
B) 827 Hz
C) 750 Hz
D) 721 Hz
E) 650 Hz

Question 43

A string with a mass per length of 2.00 g/m is stretched between two points that are 0.400 m apart.The second mode frequency of the stretched string is 50.0 Hz lower than the third mode frequency.What is the tension in the string?

A) 400 N
B) 375 N
C) 321 N
D) 281 N
E) 250 N

Question 44

An organ pipe is 60.0 cm long and is open at one end and closed at the other.The frequency of the third mode is 300 Hz higher than the frequency of the second mode.What is the velocity of sound?

A) 280 m/s
B) 300 m/s
C) 320 m/s
D) 340 m/s
E) 360 m/s

Question 45

A string with a mass per length of 2.00 gm/m is stretched with a force of 150 N between two points that are 0.500 m apart.The fundamental frequency of the stretched string is in tune with the fundamental frequency of an organ pipe filled with air and open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the length of the organ pipe?

A) 50.2 cm
B) 55.2 cm
C) 57.5 cm
D) 60.4 cm
E) 65.3 cm

Question 46

A 30 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the wavelength of the second mode?

A) 10 cm
B) 20 cm
C) 30 cm
D) 40 cm
E) 60 cm

Question 47

A string with a mass per length of 2.00 gm/m is stretched with a force of 150 N between two points that are 0.500 m apart.The fundamental frequency of the stretched string is in tune with the fundamental frequency of an organ pipe filled with air and open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.If the temperature of the air increases by 20 $^{\circ}$ C,then what is the length of the organ pipe?

A) 70.5 cm
B) 62.6 cm
C) 59.3 cm
D) 53.8 cm
E) 50.2 cm

Question 48

A string with a mass per length of 2.00 gm/m is stretched with a force of 120 N between two points that are 0.400 m apart.The fundamental frequency of the stretched string is in tune with the frequency of the second mode of an organ pipe filled with air and open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the length of the organ pipe?

A) 225 cm
B) 175 cm
C) 125 cm
D) 108 cm
E) 95.0 cm

Question 49

A 25.0 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the frequency of the fifth mode?

A) 1,550 Hz
B) 1,750 Hz
C) 2,320 Hz
D) 2,720 Hz
E) 3,170 Hz

Question 50

An organ pipe is 80.0 cm long and is open at one end and closed at the other.The frequency of the third mode is 200 Hz higher than the frequency of the second mode.What is the velocity of sound?

A) 300 m/s
B) 320 m/s
C) 340 m/s
D) 360 m/s
E) 380 m/s

Question 51

A 30 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the wavelength of the third mode?

A) 48 cm
B) 36 cm
C) 30 cm
D) 24 cm
E) 12 cm

Question 52

A 30 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the wavelength of the fundamental mode?

A) 1.4 m
B) 1.6 m
C) 1.8 m
D) 1.0 m
E) 1.2 m

Question 53

A 20 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the wavelength of the fundamental mode?

A) 40 cm
B) 60 cm
C) 80 cm
D) 43 cm
E) 75 cm

Question 54

A string with a mass per length of 2.00 gm/m is stretched with a force of 120 N between two points that are 0.400 m apart.The fundamental frequency of the stretched string is in tune with the frequency of the second mode of an organ pipe filled with air and open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.If the temperature of the air decreases by 20 $^{\circ}$ C,then what is the length of the organ pipe?

A) 75.0 cm
B) 100 cm
C) 125 cm
D) 150 cm
E) 175 cm

Question 55

A string with a mass per length of 2.00 g/m is stretched between two points that are 0.400 m apart.The third mode frequency of the stretched string is 20.0 Hz lower than the fourth mode frequency.What is the tension in the string?

A) 180 N
B) 160 N
C) 140 N
D) 120 N
E) 100 N

Question 56

A 20.0 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the frequency of the third mode?

A) 2,070 Hz
B) 2,190 Hz
C) 2,320 Hz
D) 2,450 Hz
E) 2,680 Hz

Question 57

A string with a mass per length of 2.00 gm/m is stretched with a force of 120 N between two points that are 0.400 m apart.The fundamental frequency of the stretched string is in tune with the fundamental frequency of an organ pipe filled with air and open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the length of the organ pipe?

A) 54.1 cm
B) 59.0 cm
C) 61.5 cm
D) 63.5 cm
E) 66.8 cm

Question 58

A 20.0 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the frequency of the fundamental mode?

A) 414 Hz
B) 387 Hz
C) 345 Hz
D) 302 Hz
E) 295 Hz

Question 59

A string with a mass per length of 2.00 gm/m is stretched with a force of 150 N between two points that are 0.500 m apart.The frequency of the second mode of the stretched string is in tune with the fundamental frequency of an organ pipe filled with air and open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the length of the organ pipe?

A) 43.6 cm
B) 40.1 cm
C) 37.5 cm
D) 35.6 cm
E) 30.2 cm

Question 60

A 30.0 cm long organ pipe is filled with air and is open at one end and closed at the other.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.What is the wavelength of the fifth mode?

A) 30.3 cm
B) 26.7 cm
C) 21.2 cm
D) 17.1 cm
E) 12.3 cm

Question 61

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 345.0 m/s.If the ambulance is traveling at a velocity of 24.00 m/s away from the stationary observer,then what is the frequency of the siren perceived by the observer?

A) 2,375 Hz
B) 2,306 Hz
C) 2,266 Hz
D) 2,244 Hz
E) 2,210 Hz

Question 62

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 345.0 m/s.If the observer is traveling at a velocity of 24.00 m/s away from the stationary ambulance,then what is the frequency of the siren perceived by the observer?

A) 2,375 Hz
B) 2,366 Hz
C) 2,305 Hz
D) 2,275 Hz
E) 2,233 Hz

Question 63

An organ pipe is open at both ends.The frequency of the third mode is 320 Hz higher than the frequency of the second mode.If the speed of sound is 345 m/s,then what is the length of the organ pipe?

A) 64.0 cm
B) 62.6 cm
C) 57.9 cm
D) 53.9 cm
E) 50.3 cm

Question 64

A 40.0 cm long organ pipe is filled with air at 0 $^{\circ}$ C and is open at both ends.The velocity of sound in air at 0 $^{\circ}$ C is 331 m/s.Another 40.0 cm long organ pipe is filled with air at 20 $^{\circ}$ C and is open at both ends.What is the beat frequency between the fundamental modes of the two organ pipes?

A) 20.5 Hz
B) 17.5 Hz
C) 15.6 Hz
D) 14.9 Hz
E) 12.3 Hz

Question 65

If on a given day the speed of sound increases by 5% between 8:00 am and 11:00 am,and if the temperature at 8:00 am was 21 $^{\circ}$ C,what was the temperature at 11:00 am?

A) 21.6 $^{\circ}$ C
B) 21.3 $^{\circ}$ C
C) 25.4 $^{\circ}$ C
D) 29.8 $^{\circ}$ C

Question 66

The temperature is observed to decrease from 32 $^{\circ}$ C to 23 $^{\circ}$ C during the evening of a very hot day.What is the relative change in the speed of sound over this time interval?

A) -15%
B) -28%
C) -1.5%
D) -3%

Question 67

An organ pipe is open at one end and closed at the other.The frequency of the third mode is 300 Hz higher than the frequency of the second mode.If the speed of sound is 345 m/s,then what is the length of the organ pipe?

A) 50.3 cm
B) 57.5 cm
C) 64.5 cm
D) 66.7 cm
E) 70.5 cm

Question 68

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 345.0 m/s.If the ambulance is traveling at a velocity of 24.00 m/s toward the stationary observer,then what is the frequency of the siren perceived by the observer?

A) 2,579 Hz
B) 2,540 Hz
C) 2,525 Hz
D) 2,500 Hz
E) 2,480 Hz

Question 69

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 345.0 m/s.The observer is traveling at a velocity of 24.00 m/s toward the ambulance and the ambulance is traveling at a velocity of 20.00 m/s toward the observer.What is the frequency of the siren perceived by the observer?

A) 2,489 Hz
B) 2,560 Hz
C) 2,675 Hz
D) 2,725 Hz
E) 2,830 Hz

Question 70

A 60.0 cm long organ pipe is filled with air at 15 $^{\circ}$ C and is open at both ends.The velocity of sound in air at 0.000 $^{\circ}$ C is 331 m/s.Another 60.0 cm long organ pipe is filled with air at 25.0 $^{\circ}$ C and is open at both ends.What is the beat frequency between the second modes of the two organ pipes?

A) 9.20 Hz
B) 9.33 Hz
C) 9.54 Hz
D) 9.75 Hz
E) 9.99 Hz

Question 71

A guitar string is played together with a tuning fork whose frequency is 256 Hz,and beats of 2 Hz are heard.In such a case,if initially the tension in the string is 150 N,what must the new tension be,assuming the guitar string is initially higher in frequency than the tuning fork?

A) 148 N
B) 149 N
C) 151 N
D) 152 N
E) The length of the string must be given in order to solve this problem.

Question 72

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 34.0 m/s.The observer is traveling at a velocity of 24.00 m/s toward the ambulance and the ambulance is traveling at a velocity of 24.00 m/s toward the observer.What is the frequency of the siren perceived by the observer?

A) 2,100 Hz
B) 2,250 Hz
C) 2,430 Hz
D) 2,550 Hz
E) 2,759 Hz

Question 73

A 50.0 cm long organ pipe is filled with air at 10.0 $^{\circ}$ C and is open at both ends.The velocity of sound in air at 0.00 $^{\circ}$ C is 331 m/s.Another 50.0 cm long organ pipe is filled with air at 15.0 $^{\circ}$ C and is open at both ends.What is the beat frequency between the fundamental modes of the two organ pipes?

A) 2.96 Hz
B) 2.45 Hz
C) 2.10 Hz
D) 1.94 Hz
E) 1.77 Hz

Question 74

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 345.0 m/s.The observer is traveling at a velocity of 24.00 m/s toward the ambulance and the ambulance is traveling at a velocity of 24.00 m/s away the observer.What is the frequency of the siren perceived by the observer?

A) 2,448 Hz
B) 2,424 Hz
C) 2,400 Hz
D) 2,376 Hz
E) 2,352 Hz

Question 75

An ambulance is generating a siren sound at a frequency of 2,000 Hz.The velocity of sound is 345.0 m/s.The observer and the ambulance are traveling toward each other at a velocity of 24.00 m/s.If the observer is stationary,what is the frequency of the siren perceived by the observer?

A) 2,032 Hz
B) 2,150 Hz
C) 2,220 Hz
D) 2,575 Hz
E) 2,750 Hz

Question 76

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 345.0 m/s.If the observer is traveling at a velocity of 24.00 m/s toward the stationary ambulance,then what is the frequency of the siren perceived by the observer?

A) 2,640 Hz
B) 2,567 Hz
C) 2,520 Hz
D) 2,508 Hz
E) 2,475 Hz

Question 77

An ambulance is generating a siren sound at a frequency of 2,400 Hz.The velocity of sound is 345.0 m/s.If the observer is traveling at a velocity of 24.00 m/s toward the stationary ambulance,then what is the frequency of the siren perceived by the observer?

A) 2,657 Hz
B) 2,567 Hz
C) 2,532 Hz
D) 2,500 Hz
E) 2,479 Hz

Question 78

An ambulance is generating a siren sound at a frequency of 2,000 Hz.The velocity of sound is 345.0 m/s.The observer and the ambulance are traveling toward each other at a velocity of 24.00 m/s.If the ambulance is stationary,what is the frequency of the siren perceived by the observer?

A) 2,640 Hz
B) 2,559 Hz
C) 2,324 Hz
D) 2,139 Hz
E) 2,003 Hz

Question 79

An organ pipe is open at both ends.The frequency of the fourth mode is 316 Hz higher than the frequency of the third mode.If the speed of sound is 340 m/s,then what is the length of the organ pipe?

A) 53.8 cm
B) 59.8 cm
C) 60.3 cm
D) 62.8 cm
E) 64.7 cm

Question 80

There are two identical organs with pipes having fundamental frequencies of 264.0 Hz at 20 $^{\circ}$ C.One organ is located at the front of the auditorium where the temperature is 20 $^{\circ}$ C and one at the back where the temperature in 25.0 $^{\circ}$ C.What is the beat frequency when the two organs sound this note simultaneously?

A) zero since it is the same note
B) 2.64 Hz
C) 31.2 Hz
D) 4.51 Hz