Measuring speed of sound in air

In summary, the task at hand is to measure the speed of sound in air using a microphone, signal generator, amplifier, and digital oscilloscope. A simple experiment involving a loudspeaker is not possible due to the lack of one in the lab. Suggestions have been made to use a preamp, one microphone, and two people clapping at different distances to obtain accurate readings. Google has been recommended as a resource for additional ideas, including using a watch with a second hand. The signal generator can be used to produce audio waves, but a loudspeaker is currently unavailable.
  • #1
ecy5maa
30
0
Hi.

I have been given the task to measure the speed of sound in air. The materials available are:

1. Microphone

2. Signal Generator

3. Amplifier

4. Digital Oscilloscope


I have looked through google and the simplest exp involves a loudspeaker as well. However I don't have one in the lab. Can someone suggest a method using the 4 items listed above to measure the speed of sound in air?
 
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  • #2
ecy5maa said:
Hi.

I have been given the task to measure the speed of sound in air. The materials available are:

1. Microphone

2. Signal Generator

3. Amplifier

4. Digital Oscilloscope


I have looked through google and the simplest exp involves a loudspeaker as well. However I don't have one in the lab. Can someone suggest a method using the 4 items listed above to measure the speed of sound in air?

Are you allowed to clap?
 
  • #3
Yes. The lab sheet just says we have to use a microphone and an oscilliscope. Everything else is dependent on the person doing the experiment
 
  • #4
ecy5maa said:
Yes. The lab sheet just says we have to use a microphone and an oscilliscope. Everything else is dependent on the person doing the experiment

Well there you go! That was easy.

Now, can you describe some ways to set up the experiment? What special considerations might you have about the microphone and preamp...?
 
  • #5
i tried a simple one by connecting two microphones to the oscilloscope keeping a distance x between them and clapping a distance y from both of them.

But none of my claps, or any music that i played registered any wave fluctuation
 
  • #6
ecy5maa said:
i tried a simple one by connecting two microphones to the oscilloscope keeping a distance x between them and clapping a distance y from both of them.

But none of my claps, or any music that i played registered any wave fluctuation

Did you use the preamp? It's hard to believe you aren't seeing any audio at all...
 
  • #7
nope i didnt use the preamp.

but how would i use the preamp just for a clap?
 
  • #8
ecy5maa said:
nope i didnt use the preamp.

but how would i use the preamp just for a clap?

You connect a microphone to a preamp, and monitor the output of the preamp with the 'scope. Can you think of how you could use just one microphone instead of two?
 
  • #9
So what you are saying is; I connect the microphone to the pre amp. That will amplify the sound waves from the 'clap' and then i monitor the output from the scope?

Hmm..i guess i can clap at increasing or decreasing distances from the mic ?
 
  • #10
ecy5maa said:
Hmm..i guess i can clap at increasing or decreasing distances from the mic ?

If you use only one microphone, you need one other thing that is generally available...
 
  • #11
which is ? :confused:
 
  • #12
ecy5maa said:
which is ? :confused:

It's *your* project, so think about it some. Another hint -- you could also use two people instead of two microphones...
 
  • #13
two people who clap at the same time?
 
  • #14
ecy5maa said:
two people who clap at the same time?

How would you set up that experiment?
 
  • #15
Umm...but won't i still need something to catch the sound wave the 'claps' produce?

:confused:
 
  • #16
ecy5maa said:
Umm...but won't i still need something to catch the sound wave the 'claps' produce?

:confused:

That would be the microphones and preamps, no?
 
  • #17
ohh i thought u meant without using any microphone...

So i place the mic a distance x from two people who themselves are a distance y between them. Then I ask them to both clap at the same time. and record the distance between the peaks shown on the Oscilloscope?

However, I change x or do I change y ie. the distance between the two people?
 
  • #18
ecy5maa said:
ohh i thought u meant without using any microphone...

So i place the mic a distance x from two people who themselves are a distance y between them. Then I ask them to both clap at the same time. and record the distance between the peaks shown on the Oscilloscope?

However, I change x or do I change y ie. the distance between the two people?

You are getting closer. There is a simpler arrangement of the two people that will give you a more accurate reading...
 
  • #19
im stumped :confused:
 
  • #20
ecy5maa said:
im stumped :confused:

I'm not getting the sense that you're trying very hard on this.

When I'm stumped, Google is often my friend. Have you tried googling speed of sound? Do that, and add the extra search term clap. Bet you get lots of ideas from reading that hit list. There was even one idea that I'd never seen before that let's you use a watch with a second hand! Pretty clever.
 
  • #21
Ok. Thanks never the less.
 
  • #22
ecy5maa said:
Hi.

I have been given the task to measure the speed of sound in air. The materials available are:

1. Microphone

2. Signal Generator

3. Amplifier

4. Digital Oscilloscope


I have looked through google and the simplest exp involves a loudspeaker as well. However I don't have one in the lab. Can someone suggest a method using the 4 items listed above to measure the speed of sound in air?

What's the signal generator good for ? :confused:
 
  • #23
Quinzio said:
What's the signal generator good for ? :confused:

The signal generator + loud speaker would produce audio waves.


But right now the lab does not have a loud speaker. So ill have to make do without
 

1. How is the speed of sound in air measured?

The speed of sound in air is typically measured using a technique called the "time-of-flight" method. This involves measuring the time it takes for a sound wave to travel a known distance and using that time and distance to calculate the speed of sound.

2. What factors affect the speed of sound in air?

The speed of sound in air can be affected by several factors, including temperature, humidity, and air pressure. Generally, as temperature and humidity increase, the speed of sound also increases. However, higher air pressure can actually decrease the speed of sound.

3. What is the average speed of sound in air?

The average speed of sound in air at sea level and room temperature (20°C or 68°F) is approximately 343 meters per second, or 767 miles per hour.

4. How does the speed of sound in air compare to the speed of light?

The speed of sound in air is significantly slower than the speed of light. While sound travels at approximately 343 meters per second, the speed of light is approximately 299,792,458 meters per second.

5. Can the speed of sound in air change?

Yes, the speed of sound in air can change depending on various factors such as temperature, humidity, and air pressure. It can also change depending on the medium through which the sound is traveling, as sound travels at different speeds in different materials.

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