Siren Wavelength for Car Travelling North at 29.4 m/s

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In summary, a siren wavelength refers to the distance between two consecutive peaks or troughs of a sound wave produced by a siren. It can be calculated using the formula: wavelength = speed of sound / frequency, where frequency is the number of sound waves produced per second and the speed of sound depends on the medium it is traveling through. The siren wavelength is important for a car travelling north at 29.4 m/s because it affects the perceived frequency of the siren, allowing the driver to determine the direction and proximity of the sound source. There is an inverse relationship between siren wavelength and car speed, as the car moves faster, the siren wavelength decreases. The siren wavelength is not affected by the direction of car
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srhly
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An ambulance is traveling North at 64.1 m/s, approaching a car that is also traveling North at 29.4 m/s. The ambulance driver hears his siren at a frequency of 705 cycles/s. The velocity of sound is 343 m/s. What is the wavelength at the car driver's position for the sound from the ambulance's siren? Answer in units of m.
 
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Do you know those 4 cases (actually only one useful in this problem) of Doppler effect...?Which case of the 4 does this problem correspond to?

You should always review the theory first?

Daniel.
 
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The wavelength at the car driver's position for the sound from the ambulance's siren can be calculated using the formula: wavelength = velocity / frequency. In this case, the velocity of sound is given as 343 m/s and the frequency is 705 cycles/s. Therefore, the wavelength can be calculated as:

wavelength = 343 m/s / 705 cycles/s = 0.486 m

This means that the sound waves from the ambulance's siren have a wavelength of 0.486 meters at the car driver's position. This is important to note because as the ambulance approaches the car, the wavelength of the sound waves will decrease due to the Doppler effect. This will result in a higher frequency and a higher pitch of the siren as perceived by the car driver. It is important for drivers to be aware of this effect and adjust their driving accordingly to avoid potential accidents.
 

1. What is a siren wavelength?

A siren wavelength refers to the distance between two consecutive peaks or troughs of a sound wave produced by a siren.

2. How is the siren wavelength calculated?

The siren wavelength can be calculated using the formula: wavelength = speed of sound / frequency. In this case, the frequency is the number of sound waves produced per second by the siren, and the speed of sound depends on the medium it is traveling through (for example, it is faster in air than in water).

3. Why is the siren wavelength important for a car travelling north at 29.4 m/s?

The siren wavelength is important for a car travelling north at 29.4 m/s because it affects the perceived frequency of the siren. As the car moves towards the sound source, the wavelength decreases, resulting in a higher frequency and a higher-pitched sound. This allows the driver to determine the direction and proximity of the sound source.

4. What is the relationship between siren wavelength and car speed?

There is an inverse relationship between siren wavelength and car speed. As the car moves faster, the siren wavelength decreases, resulting in a higher frequency and a higher-pitched sound. This is because the sound waves are compressed as the car moves towards the sound source.

5. How is the siren wavelength affected by the direction of car travel?

The siren wavelength is not affected by the direction of car travel. It is only affected by the speed of the car and the speed of sound in the medium it is traveling through. However, the perceived frequency of the siren may be affected depending on whether the car is moving towards or away from the sound source.

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