Measuring speed of sound in air

  • Thread starter ecy5maa
  • Start date
  • #1
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 dont have one in the lab. Can someone suggest a method using the 4 items listed above to measure the speed of sound in air?
 

Answers and Replies

  • #2
berkeman
Mentor
60,372
10,669
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 dont 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
30
0
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
berkeman
Mentor
60,372
10,669
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
30
0
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
berkeman
Mentor
60,372
10,669
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
30
0
nope i didnt use the preamp.

but how would i use the preamp just for a clap?
 
  • #8
berkeman
Mentor
60,372
10,669
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
30
0
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
berkeman
Mentor
60,372
10,669
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
30
0
which is ? :confused:
 
  • #12
berkeman
Mentor
60,372
10,669
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
30
0
two people who clap at the same time?
 
  • #14
berkeman
Mentor
60,372
10,669
two people who clap at the same time?

How would you set up that experiment?
 
  • #15
30
0
Umm...but wont i still need something to catch the sound wave the 'claps' produce?

:confused:
 
  • #16
berkeman
Mentor
60,372
10,669
Umm...but wont i still need something to catch the sound wave the 'claps' produce?

:confused:

That would be the microphones and preamps, no?
 
  • #17
30
0
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
berkeman
Mentor
60,372
10,669
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
30
0
im stumped :confused:
 
  • #20
berkeman
Mentor
60,372
10,669
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 lets you use a watch with a second hand! Pretty clever.
 
  • #21
30
0
Ok. Thanks never the less.
 
  • #22
558
1
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 dont 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
30
0
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
 

Related Threads on Measuring speed of sound in air

  • Last Post
Replies
0
Views
1K
  • Last Post
Replies
10
Views
4K
  • Last Post
Replies
4
Views
1K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
10
Views
3K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
7
Views
7K
  • Last Post
Replies
1
Views
519
  • Last Post
Replies
2
Views
1K
Replies
1
Views
8K
Top