# In this equation, vd is the speed of the detector, and vs is the speed of the source. Also, fs is the frequency of the source, and fd is the frequency of the detector. If the detector moves toward the

76,389 results

1. ### physics

In this equation, vd is the speed of the detector, and vs is the speed of the source. Also, fs is the frequency of the source, and fd is the frequency of the detector. If the detector moves toward the source, vd is positive. If the source moves toward the detector, vs is ...
2. ### physics

a source emits 1700Hz frequency travelling at a speed of 70m/s. A detector is placed 200m away. What is the frequency detected by the detector when the source is closest to it? Also find the distance between them when the detector detects the frequency to be 1200Hz. Velocity ...
3. ### Physics

A vibrator in a ripple tank vibrates with a frequency of 3.0 Hz and an amplitude of 2.5 cm. The resulting waves travel away from the source with a speed of 2.5 cm/s, passing under various markers floating on the water. (a)In what direction(s) do the marker move? (b) With what ...
4. ### Physics

A vibrator in a ripple tank vibrates with a frequency of 3.0 Hz and an amplitude of 2.5 cm. The resulting waves travel away from the source with a speed of 2.5 cm/s, passing under various markers floating on the water. (a)In what direction(s) do the marker move? (b) With what ...
5. ### Physics

A vibrator in a ripple tank vibrates with a frequency of 3.0 Hz and an amplitude of 2.5 cm. The resulting waves travel away from the source with a speed of 2.5 cm/s, passing under various markers floating on the water. (a)In what direction(s) do the marker move? (b) With what ...
6. ### Physics: Wave Motion

A vibrator in a ripple tank vibrates with a frequency of 3.0 Hz and an amplitude of 2.5 cm. The resulting waves travel away from the source with a speed of 2.5 cm/s, passing under various markers floating on the water. (a)In what direction(s) do the marker move? (b) With what ...
7. ### Physics:Wave Motion

A vibrator in a ripple tank vibrates with a frequency of 3.0 Hz and an amplitude of 2.5 cm. The resulting waves travel away from the source with a speed of 2.5 cm/s, passing under various markers floating on the water. (a)In what direction(s) do the marker move? (b) With what ...
8. ### Physics

Exploration 3: A Moving Source at Different Velocities Procedure 1. Set Wave speed to 10.0 cm/s and Source frequency to 1.0 Hz. Place the detector anywhere. 2. Set Source speed to 6.0 cm/s. Select Go. Sketch the resulting wave-front pattern on a separate sheet of paper. 3. ...
9. ### physics

1)As a sound source moves away from a stationary observer, the number of waves will. A)increase B)decrease C)remain the same D)need to know the speed of the source (answer:decrease.) As the detector recedes from the source, the relative velocity is smaller, resulting in a ...
10. ### Physics

1)As a sound source moves away from a stationary observer, the number of waves will. A)increase B)decrease C)remain the same D)need to know the speed of the source (answer:decrease.) As the detector recedes from the source, the relative velocity is smaller, resulting in a ...
11. ### Physics

Resonance in a system, such as a string fixed at both ends, occurs when a) it is oscillating in simpler harmonic motion b) its frequency is the same as the frequency of an external source c) its frequency is greater than the frequency of an external source d) its frequency is ...
12. ### Physics

Three sources of sound are distributed along a line, as shown in the figure. v is the speed of sound. Source A is at rest, and it emits sound waves with a frequency of 480 Hz. Source B is traveling at v/5 to the right, and it emits sound waves with a frequency of 960 Hz. ...
13. ### Physics _ College

A 50 cm long hollow glass cylinder is open at both ends and is suspended in air. A source of sounds that produces a pure frequency is placed close to one end of the tube. The frequency is placed close to one end of the tube. The frequency of the sound source is slowly ...
14. ### PHYSICS

A 50cm long hollow glass cylinder is open at both ends and is suspended in air. A source o sound that produces a pure frequency is placed close to one end of the tube. The frequency of the sound is slowly increased from a very low value. The tube is first observed to resonate ...
15. ### Physics

1. A train whistle has a frequency of 1000 Hz. If the train is speeding at a velocity of 60 km/h past a stationary railroad crossing attendant, what is the apparent frequency a) as the train approaches him, b) as it moves away from him? Assume speed of sound to be 350 m/s. 2. ...
16. ### physics

A speeding car is pulling away from a police car. The police car is moving at 30 m/s. The radar gun in the police car emits an electromagnetic wave with a frequency of 20.0 x 10^9 Hz. The wave reflects from the speeding car and returns to the police car where the frequency is ...
17. ### phy

Doppler ultrasound is used to measure the speed of blood flow. If the speed of the red blood cells is v, the speed of sound in blood is u, the ultrasound source emits waves of frequency f, and we assume that the blood cells are moving directly toward the ultrasound source, ...
18. ### physics

If the sound waves detected by the dector is the same as the frequency of the source, what can we conclude about the motion of the source and detector?
19. ### Physics

A source passing a stationary observer is emitting a frequency of 560 Hz. If the speed of sound is 345 m/s, what must speed of the source be if the frequency speed is 480 hz? Here's what I've tried... Fo=480 Hz FObs = 480 + 560 VSource = ?(x) Vsound = 345 m/s I try to ...
20. ### physics

An observer rides with a moving sound source directly toward a large vertical wall. The vehicle has a constant speed of 10m/s and the source has a frequency of 150Hz. What beat frequency is heard by the observer as a result of the combination of the direct and reflected sounds?
21. ### physics pls help

A sound source producing 1.00-{\rm kHz} waves moves toward a stationary listener atone-half the speed of sound. The frequency that the listener will hear is2000 Hz. when the source is stationary and the listener moves towardthe source at one-half the speed of sound, the ...
22. ### physics

A stationary motion detector sends sound waves of frequency 0.0953 MHz toward a truck approaching at a speed of 42.6 m/s. What is the frequency of the waves reflected back to the detector? (Take the speed of sound to be 343 m/s.)
23. ### Intergarted Science

I had a couple of questions on the topic of Waves-Sound and Light. 1. What is the source of all waves? *Vibration* 2. In one word, what is it that moves from source to receiver in a wave motion? *Energy* 3. Does the medium in which a wave travels move with the wave? *No* 4. ...
24. ### physics

An acoustic burglar alarm consists of a source emitting waves of frequency 28.0 kHz. What is the beat frequency between the source waves and the waves reflected from an intruder walking at an average speed of 0.095 m/s directly away from the alarm?
25. ### Waves-Science

I had a couple of questions on the topic of Waves-Sound and Light. 1. What is the source of all waves? *Vibration* 2. In one word, what is it that moves from source to receiver in a wave motion? *Energy* 3. Does the medium in which a wave travels move with the wave? *No* 4. ...
26. ### physics

a source of sound id traveling towards a stationary observer .The frequency of sound is heard by the observer is 25% more that the actual frequency.If the speed of sound is v,that of the source is options: 1.v/4 2.v/5
27. ### Physics

Two eagles fly directly toward one another, the first at 13 m/s and the second at 21 m/s. Both screech, the first emitting a frequency of 3200 Hz and the second, a frequency of 3800 Hz. What frequencies do they hear if the speed of sound is 345 m/s? (Tip: keep 4 significant ...
28. ### physics(URGENT!!!!!)

A source of sound emits waves at a frequency f= 650 Hz. An observer is located at a distance d= 170 m from the source. Use u=340 m/s for the speed of sound. (a) Assume completely still air. How many wavefronts (full waves) N are there between the source and the observer? N= ...
29. ### Physics

Blood flow rates in the umbilical cord can be found by measuring the Doppler shift of the ultrasound signal reflected by the red blood cells. If the source emits a frequency f, what is the measured reflected frequency fR? Assume that all of the red blood cells move directly ...
30. ### physics, doppler effect

"A source of sound of frequency f0 moves horizontally at constant speed u in the x direction at a distance h above the ground. An observer is situated on the ground at the point x=0 (the source passes over this point at t=0). Show that the signal received at any time Tr at the...
31. ### physics

A siren mounted on the roof of a firehouse emits sound at a frequency of 900 Hz. A steady wind is blowing with a speed of 15 m/s. Take the speed of sound in calm air to be 343 m/s. (c) Firefighters are approaching the siren from various directions at 15.0 m/s. What frequency ...
32. ### physics

A train at rest emits a sound at a frequency of 1089 Hz. An observer in a car travels away from the sound source at a speed of 30.7 m/s. What is the frequency heard by the observer? Assume the speed of sound in air to be 343 m/s.
33. ### physic

A source of sound emits waves at a frequency 650 Hz. An observer is located at a distance 190 m from the source. Use m/s for the speed of sound. (a) Assume completely still air. How many wavefronts (full waves) are there between the source and the observer? unanswered (b) If ...
34. ### Physics

In a resonance-tube containing air, the source of sound is a small loudspeaker driven by a variable-frequency oscillator. The distance between successive antinodes is 10 cm for a frequency of 1625 Hz. When the frequency is slowly reduced, the standing wave pattern at first ...
35. ### physics

if a man moving away with the speed of 0.5 of sound from a stationary sound source producing a sound of frequency , he would hear a sound of frequency
36. ### physics

You are riding your bicycle directly away from a stationary source of sound and hear a frequency that is 2.5% lower than the emitted frequency. The speed of sound at the temperature that day is 339 m/s. What is your speed? f = f0(v + vo)/v. Here, vo is the unknown. f = fo*.985...
37. ### Physics

Which of the following statements correctly describes the changes that occur in a sound wave, as it passes from cool air into warmer air? A) speed,wavelength and frequency all increase B) speed, wavelength increase; frequency decreases C) speed, wavelength increase; frequency ...
38. ### physics

1)As a sound source moves away from a stationary observer, the number of waves will. decrease 2)How fast should a car move toward you for the car's horn to sound 2.88% higher in frequency than when the car is stationary? The speed of sound is 343 m/s. fs(v-vd/v-vs) 343(1/1-987...
39. ### Literacy 2

1. Which of the following question should you ask to help determine the suitability of a source? A Who is the source's audience B Can i print this source c Is this source also included in a book D who disagreed with this source Answer A
40. ### physics

Doubling the frequency of a wave source doubles the speed of the waves. ( True or False)
41. ### physics

1)As a sound source moves away from a stationary observer, the number of waves will. decrease 2)How fast should a car move toward you for the car's horn to sound 2.88% higher in frequency than when the car is stationary? The speed of sound is 343 m/s. fs(v-vd/v-vs) 343(1/1-987...
42. ### Physics doppler effect

A radar device emits microwaves with a frequency of 4.73E+9 Hz. When the waves are reflected from a van moving directly away from the emitter, the beat frequency between the source wave and the reflected wave is 751 beats per second. What is the speed of the van? (Note: ...
43. ### Physics

Find the beat frequency produced by an 686 Hz source and an 894 Hz source.
44. ### Physics

Ultrasound reflected from an oncoming bloodstream that is moving at 30 cm/s is mixed with the original frequency of 1.3 MHz to produce beats. What is the beat frequency? (Velocity of sound in blood = 1540 m/s.) Beat frequency = Hz HELP: This problem involves two Doppler shifts...
45. ### Physics

Someone has already posted this question, but their's was never answered, so hopefully someone can answer this. Thanks. An interference pattern is set up by two point sources of the same frequency, vibrating in phase with one another. A point on the second nodal line is 50.0 ...

Can the voltage across any of the three components in the R-L-C series circuit ever be larger than the maximum voltage supplied by the AC source? That maximum voltage is 50 volts in this situation. Also, does Kirchoff's loop rule apply to this circuit? In other words, is the ...
47. ### physics, help with circuits please!

Can the voltage across any of the three components in the R-L-C series circuit ever be larger than the maximum voltage supplied by the AC source? That maximum voltage is 50 volts in this situation. Also, does Kirchoff's loop rule apply to this circuit? In other words, is the ...
48. ### Physics

A train blows its horn as it approaches a crossing. A.) if the train engineer observes a frequency of 125Hz and a stationary observer at the crossing observes a frequency of 132Hz, what is the speed of the train? (The speed of sound is 330m/sec on this day). B.) what frequency...
49. ### Physics

When you approach a blinking source of light, the frequency of its blinking is seen to: decrease, increase, or remain the same always. I THINK IT IS INCREASING. If you are traveling at close to the speed of light and shine a flashlight out in front of you, a third observer at ...

A sound of 7 kHz frequency is well within the normal hearing range of most people. True. False. << 2. Sound is a transverse compression wave. True. False.<< 3. The decibel level of a sound can have a negative value. True.<< False. 4. The Doppler effect occurs...
51. ### Physics

Question about doppler effect: How do you solve when it gives you percentage value? (Q 1) How do you calculate for doppler effect when the listener is moving instead of the source of sound? (Q 2) Questions 1. As a racing car zooms by you, its pitch decreases by 20%. If the ...
52. ### Physics Questions!

An interference pattern is set up by two point sources of the same frequency, vibrating in phase with one another. A point on the second nodal line is 50.0 cm from one source and 59 cm from the other. The speed of the waves is 35 cm/s. Calculate the frequency of the sources. I...
53. ### physics

A source delivers an AC voltage of the form Δv = (89.0 V) sin (70πt), where Δv is in volts and t is in seconds, to a capacitor. The maximum current in the circuit is 0.460 A. Find the following. (a) Find the rms voltage of the source. (b) Find the frequency of the source. (...
54. ### Physics

Let f be the frequency, v wav the speed, and T the period of a sinusoidal traveling wave. The correct relationship is: a)f=1/T b)f=vwav + T c)f=vwavT d)f=vwav/T e)f=T/vwav My thoughts: I think the answer is D.Since frequency is equal to T=1/f so f=1/T. Vwav is connected to f ...
55. ### Doogleberry Physcis

In an L-R-C series circuit, the resistance is 380 Ohms, the inductance is 0.400 H, and the capacitance is 2.00×10−2 uF. What is the resonant frequency of the circuit? (omega naught) The capacitor can withstand a peak voltage of 570 volts. If the voltage source operates ...
56. ### physics

A skipper on a boat notices wave crests passing his anchor chain every 9 s. He estimates the distance between wave crests to be 15 m. He also correctly estimates the speed of the waves. What is this speed? Wavelenght* frequency= wave speed remember that frequency here is 1wave...
57. ### Science

A wave is determined to have a frequency of 12 Hz and a wavelength of 8.5 meters. What is the speed of the wave? Show all of your work, including the formula and correct units. I am not really sure how to set up the equation for this. Speed= wavelength x frequency... So would ...
58. ### Physics

Michelson used a rotating eight sided mirrored "wheel" to determine speed of light. In this case the mirror is rotated at a certain frequency which allows light to travel from the source, reflect off the mirrored wheel and into the observers eyes. What is the minimum frequency...
59. ### physics

A sound wave travels in air at a frequency of 500 Hz. If part of the wave travels from air into water, does its frequency change? Does its wavelength change? Note that the speed of sound in air is about 340 m/s, whereas the speed of osund in water is about 1500 m/s. Frequency ...
60. ### frequency-physics

Two sirens A and B are sounding so that the frequency from A is twice the frequency from B. Compared with the speed of sound from A, which of the following statements is true?
61. ### science

apparent change in wavelength of sound waves is 2.5cm when the source of sound is approaching stationary listener with velocity 8cm/s.Apparent decrease in the frequency of source when observer recedes from the same source at rest with a velocity of 30m/s is (velocity of sound...
62. ### Physics Sound Waves

A fire truck emitting a 450 Hz signal passes by a stationary detector. The difference in frequency measured by the detector is 58 Hz. If the speed of sound is 345 m/s, how fast is the fire truck moving? The answer should be 22 m/s but I don't even know where to start. Could ...
63. ### Physics - Doppler Effect

The siren in an ambulance has a frequency (according to you) of 1100 hz as it moves towards you at a speed v. It then makes a u-turn and travels away from you with a speed v, and you hear a frequency of 950 hz. What is the final speed v of the siren?
64. ### physical

You are traveling in a car toward a hill at a speed of 42.1 mph. The car's horn emits sound waves of frequency 251 Hz, which move with a speed of 343 m/s. a) Determine the frequency with which the waves strike the hill. b) What is the frequency of the reflected sound waves you...
65. ### physics

You are traveling in a car toward a hill at a speed of 40.8 mph. The car's horn emits sound waves of frequency 243 Hz, which move with a speed of 340 m/s.The frequency with which the waves strike the hill is 254.7Hz and the frequency of the reflected sound waves you hear 271.2...
66. ### physics

Two motorcycles are traveling in opposite directions at the same speed when one of the cyclists blasts his horn, which has frequency of 544 Hz. The other cyclist hears the frequency as 522 Hz. If the speed of sound in air is 344 m/s, what is the speed of the motorcycles
67. ### Physics

A source produces 2000 sound waves in 4 seconds. The distance between two consecutive compressions is 55cm. Find the frequency, wavelength and speed of sound wave
68. ### physics

A train moving at a constant speed is passing a stationary observer on a platform. a flute player is playing a note with frequency of 940Hz. after the flute has passed, the observer hears the sound frequency of 915Hz. What is the speed of the train? The speed of sound in air ...
69. ### physics

Two identical sources S1 and S2 are moving towards an observer P. The two sound sources S1 and S2 produce notes of frequency 500hz. If the speed of S1 and S2 are 20ms-1 and 23ms-1 respectively, calculate the beat frequency heard by P. (Speed of sound = 340ms-1) I don't ...
70. ### physics

A small source O of electromagnetic waves is placed some distance from a plane metal reflector M. A receiver R, moving between O and M along the line normal to the reflector, detects successive maximum and minimum readings on the meter joined to it. (a) explain why these ...
71. ### physics

A stationary speaker is emitting a sound of frequency 1330 Hz. The air has a temperature of ^oF. Taking right to be positive, a person is moving toward the source (to the left) at 8.2 \frac{m}{s}. The person will hear a frequency of ... f =
72. ### physics

Let f be the frequency, v wav the speed, and T the period of a sinusoidal traveling wave. The correct relationship is: a)f=1/T b)f=vwav + T c)f=vwavT d)f=vwav/T e)f=T/vwav My thoughts: I think the answer is D.Since frequency is equal to T=1/f so f=1/T. Vwav is connected to f ...
73. ### phys

An observer detects an apparent frequency of 505 hz coming from a 500 hz source. Which is true? a. the observer is moving due east, away from the stationary source b. the source is moving due west, away from the stationary observer c. the souce and the observer are moving away...
74. ### Physics

A 75 W light source consumes 75 W of electric power. Typically only about 5% of this energy is emitted as visible light of wavelength 600 nm. (a) Calculate the frequency of the emitted visible light. (b) How many photons per second of visible light does the source emit? (c) Is...
75. ### physics

An observer detects an apparent frequency of 505 hz coming from a 500 hz source. Which is true? a. the observer is moving due east, away from the stationary source b. the source is moving due west, away from the stationary observer c. the souce and the observer are moving away...
76. ### physics

The siren on an ambulance is emitting a sound whose frequency is 2421 Hz. The speed of sound is 343 m/s. (a) If the ambulance is stationary and you (the "observer") are sitting in a parked car, what are the wavelength and the frequency of the sound you hear? (b) Suppose that ...
77. ### physics

I have the speed of a light source in plexiglass and I need to find the change in frequency from air to plexiglass and the change in wavelength.
78. ### physics

A 75 W light source consumes 75 W of electric power. Typically only about 5% of this energy is emitted as visible light of wavelength 600 nm. (a) Calculate the frequency of the emitted visible light. (b) How many photons per second of visible light does the source emit? (c) Is...
79. ### Physical science

A wave travels along a string at a speed of 1,5m 1s.if the frequency of the source of the wave is 7,5hz,calculate:(a)the wavelength of the wave..(b)the period of the wave
80. ### Science - Waves - Sci. Notation

I know that the formula to calculate the speed of light is c=fλ. F is the frequency, c is the speed, and λ is the wavelength. So how do I calculate the wavelength of a purple light with a frequency of 750 * 10^12 HZ. Frequency is measured in HZ. The speed is measured...
81. ### physics

What effect does increasing each of the following have on the wavelength of a wave? a)amplitude, if speed is constant b)speed, if frequency is constant c)frequency, if speed is constant
82. ### science

A sound source of frequency 170Hz is placed near a wall. A man walking from the source towards the wall. Find that there is a periodic rise and fall of sound intensity?
83. ### Physics

How do you calculate the wave speed of waves that are 0.15 m apart, and have a frequency of 2 Hz? Wavelength is given, frequency is given. frequency*wavelength = wave speed. Thanks a whole lot

Two trains on separate tracks move toward one another. Train 1 has a speed of 125 km/h and train 2 a speed of 100.0 km/h. Train 2 blows its horn, emitting a frequency of 500 Hz. What is the frequency heard by the engineer on train 1? (Assume the speed of sound is 345 m/s.)
85. ### Physics

Light is an electromagnetic wave and travels at a speed of 3.00 108 m/s. The human eye is most sensitive to yellow-green light, which has a wavelength of 5.58 10-7 m. What is the frequency of this light? Ever heard of the equation (wavelength) x (frequency) = wave speed? Use ...

You are traveling in a car toward a hill at a speed of 40.8 mph. The car's horn emits sound waves of frequency 243 Hz, which move with a speed of 340 m/s.The frequency with which the waves strike the hill is 254.7Hz and the frequency of the reflected sound waves you hear 271.2...

You are traveling in a car toward a hill at a speed of 40.8 mph. The car's horn emits sound waves of frequency 243 Hz, which move with a speed of 340 m/s.The frequency with which the waves strike the hill is 254.7Hz and the frequency of the reflected sound waves you hear 271.2...
88. ### physics

Speed in air is 340m.s Siren of ambulance emits waves of frequency 980Hz A detector at the scene measures the frequency as 1050Hz h0w d0 I w0rk this 0ut 1050 = 340 / 340 - vs (980) 1050 = 1 - vs (980) 1050 = -vs (980) 1050 + vs = 980 1050/1050 + vs = 980 / 1050 vs = 980 / 1050...
89. ### physics

A harpsichord string of length 1.60 m and linear mass density 25.0 mg/m vibrates at a (fundamental) frequency of 450.0 Hz. (a) What is the speed of the transverse string waves in m? (b) What is the tension in N? (c) What are the wavelength and frequency of the sound wave in ...
90. ### Physics

Tsunamis are fast-moving waves often generated by underwater earthquakes. In the deep ocean their amplitude is barely noticable, but upon reaching shore, they can rise up to the astonishing height of a six-story building. One tsunami, generated off the Aleutian islands in ...
91. ### physics

an automobile is travelling towards you at a speed 25.0m/s. When you measure the frequency of its horn, you obtain a value of 26Hz. If the actual frequency of the horn is known to be 240Hz, calculate speed of sound in air? answer is 325m/s
92. ### physics

A vibrating stretched string has length 31 cm, mass 19 grams and is under a tension of 38 newtons. What is the frequency of its 3rd harmonic? If the source of the wave is an open organ pipe of the same length as the wire, what would be the frequency of the 4 th harmonic?

A sinusoidal wave travels along a string. The time for a particle to move from maximum displacement to zero is 0.170s. What are the a)period b)frequency c) the wavelength is 1.40m what is the wave speed? ok I know i need the equation T=1/f and the wave equation y=YSIN{kx-wt...
94. ### physics

As a train moves away from you, the frequency of its whistle is determined to be 475Hz. If the actual frequency was 500 Hz and the speed of sound in air is 350m/s, what is the Train's speed? answer is 18.4m/s please show and explain steps
95. ### Physics

A harpsichord string of length 1.50 m and linear mass density 26.0 mg/m vibrates at a (fundamental) frequency of 460.0 Hz. (a) What is the speed of the transverse string waves? m/s (b) What is the tension? N (c) What are the wavelength and frequency of the sound wave in air ...
96. ### English

I need a peer reviewed journal source and a magazine article source on bureacracy model of Criminal Justice..thank you also what is the difference in an internet source and a web page?
97. ### solar science physics

Which of the following statements is NOT true about solar inverters? A stand-alone inverter is supposed to work as an AC voltage source for a specified range of AC loads. An ideal grid-tied inverter has its operational voltage and frequency synchronized with those of the grid...
98. ### Physics

You are flying in an ultra-light aircraft at a speed of 41.4 m/s. An eagle, whose speed is 21.7 m/s, is flying directly toward you. Each of the given speeds is relative to the ground. The eagle emits a shrill cry whose frequency is 3680 Hz. The speed of sound is 330 m/s. What ...
99. ### physics

A vibrating stretched string has length 139 cm, mass 38 grams and is under a tension of 38 newtons. What is the frequency of its 5th overtone? f_{6} = If the source of the wave is an open organ pipe of the same length as the wire and the temperature of the air is 20^oC, what ...
100. ### Physics

The wavelength in air of a sound is 5 m. (a) What is the frequency of the sound? Sound can have any frequency. It is the SPEED of sound that remains constant, independent of frequency, at a given temperature.