1. G

    Why does resonant frequency become lower as water is added to a bottle?

    Hello! I am an IB student currently working on my Internal Assessment, which is an investigation on the relationship between the volume of water in a glass bottle and the frequency of the sound made when the bottle is hit with a metal knife. I have collected my data, and found that the...
  2. C

    Sound and how it is perceived in small or large rooms

    Hello Physicists! I am a newly qualified lawyer from England and a work-related issue has had me wondering about a physics question for ages - so much so that I have joined this forum just to find an answer from people more knowledgeable than myself in the subject. Just a bit of...
  3. P

    Manipulating Sound Pressure Level

    I've performed an experiment on guitar tone - ive used a fourier analysis to find the different frequency components. The idea of this is to find the sound pressure level of the consonant intervals present in a guitar tone and compare it to the SPL of the dissonant intervals. I have found the...
  4. avito009

    Sound Waves and String Theory.

    Is the basic idea of string theory that all particles are tiny vibrating strings inspired from sonic boom? A sonic boom is the sound associated with the shock waves created whenever an object traveling through the air travels faster than the speed of sound. Sonic booms generate significant...
  5. G

    Sound Localization using multilateration?

    Hello. I'm working on a project, where I'm trying to locate the position of a sound source. I've got an array of 4 microphones, 3 in a triangle and one out of plane. The microphones are all connected to a micro-controller which can accurately time stamp the incoming signals. Since the time the...
  6. J

    Speed of sound in water

    For a science project, I need to measure the speed of sound in water. Obviously, I don't have any fancy equipment to do this so I came up with a set up I'm not sure will work: I have a PVC cut to 29.8 cm long. I attached two thin pieces of glass (a screen cover for a phone) on each end to...
  7. TyrannosaurusWreck

    Sound Level

    Hi guys, I'm back.... So I had this problem: Jane and Sam alternately pound a railroad spike into a tie with their hammers. The crew chief has a migraine, and notes that Jane's hammer blows cause a sound with intensity 5.0 times greater than the sound that Sam makes when he swings his...
  8. K

    Calculate sound generated from orifice flow

    Hi, I need help to calculate the sound which is generated as the fluid is flowing through the pipe connecting the two reservoir. (the flow direction is 1-2-3) I know every parameters in the system. What will I get if I multiply Q*deltaP? By dimensional analyses, this will give me J/s...
  9. A

    harmonic motion

    hello, I have some problem with this exercise. can someone help me and illustrate the solution ? thanks the cone of a loudspeaker vibrates in SHM at frequecy of 262Hz. the amplitude at the center of the cone is A=1.5X10^-4m and t=0 and x=A (amplitude). 1) what equation describes the...
  10. avito009

    Explain sound to a kid.

    What is sound? Sound is vibrations that travel through the air or another medium and can be heard when they reach a person's or animal's ear. We can show this kid a car that plays loud music. This car vibrates so you can say it is shaking because sound is vibration. Is my observation...
  11. N


    How and why does loudness of sound depend on the medium?
  12. A

    The Science of Sound - Chapter 6 - 4E

    if two sounds differ in level by 46dB, What is the ratio of their sound pressures? their inrensities? can u halp me to solve? please
  13. kelsiu

    How can shock waves travel faster than sound?

    Shock wave is caused by the disturbance of air by the airplane. When it propagate the mechanism should be the same as that of longitudinal sound wave. Why sometimes it can travel faster than sound? (also see: Shock Waves - The Physics Hypertextbook )
  14. N

    interference of sound

    Consider the conditions of interference of sound. I think it is not possible, after some interval of time, superposition of waves of sound will cause constructive interference, and after another interval of time it will cause destructive interference. If superposition of waves creates...
  15. N

    sound of falling water and bucket

    If a bucket is hold under a tap and the tap is open to full the bucket with water, is it possible to understand from the sound of falling water either the bucket is full or not? Are you able to give explanation behind this?
  16. P

    Why does touching a guitar string make it sound different to pressing down on it?

    I assume it has something to do with nodal planes etc., but I'm not entirely sure what the exact physics behind producing these harmonics is. Thanks!
  17. S

    Finding the frequency of a wave.

    A siren rings with 1200Hz frequency. A wind blows with 55m/s from the siren toward a man 1km away. In what frequency will the man hear it if the speed of sound is 330m/s? I found the wavelength first. Then the speed which is sound + wind velocity. Next I calculated the frequency which is 1400Hz...
  18. S

    (HELP) How to smash ice or glass with sound

    Hi everyone! for a marketing campaign we want to shatter ice or glass using sound - like when in films someone screams and all glass windows break..Is this feasible and how would you go by doing it? Any help would be much appreciated! Thanks :)
  19. L

    Apparent frequncy of sound heard

    A car is moving in a straight line at 30m/s approaches a stationary source which emits sound of freqeuncy 5000hz. If the speed of sound is 330m/s . The apparent frequncy received by car is ((330+30)/ 330) x 5000= 5455hz. What 's the frequency reflected form the car? the ans given is 6001hz...
  20. L

    Fundamental frequency of guitar string vs fundamental note of sound

    how to solve this? the ans is 352, 704 and 1056hz i have no idea. can someone help ? thanks!