- #1
Vrbic
- 407
- 18
I have 3 question:
1) How whistle produces a sound? I mean sport whistle with small ball inside.
2) How we whistle (by mouth)?
3) If you have a hole in exhaust tube in car. Many people say to me: "It is louder when the car drove long time. (a tube is hotter)" My easy question is, why? And what causes the noise when it is hotter and not cold? (if it is true...)
I know what is a sound. It is mechanical vibration of air. A change of pressure of air.
For case 1) I believe that the small ball is very important and I guess that when the ball is moving in the whistle it opens and closes a hole and also flow of air out and it changes the pressure and causes a sound wave. Do you agree?
In case 2) I can't see any moving mechanism, so in this case I have no clue. Same as in question 3).
Thank you for your response and discusion ;)
1) How whistle produces a sound? I mean sport whistle with small ball inside.
2) How we whistle (by mouth)?
3) If you have a hole in exhaust tube in car. Many people say to me: "It is louder when the car drove long time. (a tube is hotter)" My easy question is, why? And what causes the noise when it is hotter and not cold? (if it is true...)
I know what is a sound. It is mechanical vibration of air. A change of pressure of air.
For case 1) I believe that the small ball is very important and I guess that when the ball is moving in the whistle it opens and closes a hole and also flow of air out and it changes the pressure and causes a sound wave. Do you agree?
In case 2) I can't see any moving mechanism, so in this case I have no clue. Same as in question 3).
Thank you for your response and discusion ;)