How Long Should an Organ Pipe Be to Resonate at 16.4 Hz?

In summary, the conversation discusses finding the shortest organ pipe that will resonate at a given frequency and the pitch of the same pipe when closed. The conversation also recommends dropping equations and instead using a sketch to better understand the physics behind the problem. This approach will not only help solve this specific problem, but also build a better understanding for future problems.
  • #1
viciousp
51
0

Homework Statement


The Lowest note on an organ is 16.4 Hz.
a. What is the shortest pen organ that will resonate at this frequency
b. What is the pitch of the same organ pipe is closed

Homework Equations


f=V(n)/2L, n=1,2,3..
f=V(n)/4L, n-1,3,5...

The Attempt at a Solution


I understand how to do this problem , such as setting up the equation as 16.4=V(1)/2L and solve for V then you should get 16.4Hz= 32.8L/2L, but with that any L short of zero can work. I am thinking that there is not enough information to solve this problem anyone else have an idea?
 
Physics news on Phys.org
  • #2
If you had to explain to someone who'd not done this part of a physics course what each of the letters in your equations (f, V, n and L) mean, what would you say?My recommendation would be to drop these equations. Draw the organ pipe and the wave / part-wave, then continue the sketch so that a whole wavelength is included.

That way, you can actually see how the wave and pipe relate to each other. This breaks the problem down into simpler problems that you can already do. And, most importantly, it helps you to understand the physics rather than plucking some equations from a book and throwing numbers at them. So you'll be able to use your understanding to do other problems in the future.
 
  • #3


You are correct that there is not enough information to solve this problem. In order to determine the length of the pipe, we would also need to know the speed of sound in the medium (in this case, air). Additionally, the type of pipe (open or closed) would also affect the equation used to solve for the length. It is important to have all necessary information in order to accurately solve a problem.
 

1. What is the difference between an open and a closed pipe?

An open pipe refers to a pipe that is open at both ends, allowing air to freely enter and exit. A closed pipe, on the other hand, is sealed at one end and open at the other, creating a resonant cavity.

2. What is the significance of open and closed pipes in acoustics?

Open and closed pipes have different acoustic properties, affecting the sound that is produced. Open pipes produce higher pitched sounds, while closed pipes produce lower pitched sounds. This is due to the different modes of vibration that occur in each type of pipe.

3. How do open and closed pipes affect the pitch of wind instruments?

The length of the pipe determines the pitch of a wind instrument. In open pipes, the pitch is determined by the length of the pipe, while in closed pipes, the pitch is determined by the length of the closed end of the pipe. This is why instruments like flutes and clarinets (open pipes) produce higher pitched sounds than instruments like trumpets and tubas (closed pipes).

4. Can open and closed pipes be used interchangeably in musical instruments?

No, open and closed pipes cannot be used interchangeably in musical instruments. The design and construction of an instrument is specifically tailored to either an open or a closed pipe, and using the wrong type can result in incorrect pitch and tone quality.

5. How do open and closed pipes affect the speed of sound?

The speed of sound is faster in open pipes compared to closed pipes. This is because in open pipes, the air molecules can freely move in and out, allowing for faster propagation of sound waves. In closed pipes, the air molecules are more restricted, resulting in a slower speed of sound.

Similar threads

  • Introductory Physics Homework Help
Replies
3
Views
2K
Replies
10
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
4K
  • Introductory Physics Homework Help
Replies
10
Views
3K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
7
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
3K
  • Introductory Physics Homework Help
Replies
3
Views
3K
  • Introductory Physics Homework Help
Replies
14
Views
1K
Back
Top