You're in a diner eating a perfectly adequate meal when a 0.001 W speaker located 2 m away from you begins playing insufferable pop music. How loud (in dB) is the music where you are sitting? How far away should you ask to move if you want the music to be 60 dB at your new table? Right as the singer holds an unnecessarily high note with a frequency of 2000 Hz, the speaker glitches out and starts skipping so that the note plays over and over again. If the speed of sound in the diner is 330 m/s, what is the wavelength of her note?
Properties of sound
A sound wave is a mechanical wave (or mechanical vibration) that transit through media such as gas (air), liquid (water), and solid (wood).
Quality Of Sound
A sound or a sound wave is defined as the energy produced due to the vibrations of particles in a medium. When any medium produces a disturbance or vibrations, it causes a movement in the air particles which produces sound waves. Molecules in the air vibrate about a certain average position and create compressions and rarefactions. This is called pitch which is defined as the frequency of sound. The frequency is defined as the number of oscillations in pressure per second.
Categories of Sound Wave
People perceive sound in different ways, like a medico student takes sound as vibration produced by objects reaching the human eardrum. A physicist perceives sound as vibration produced by an object, which produces disturbances in nearby air molecules that travel further. Both of them describe it as vibration generated by an object, the difference is one talks about how it is received and other deals with how it travels and propagates across various mediums.
You're in a diner eating a perfectly adequate meal when a 0.001 W speaker located 2 m away from you begins playing insufferable pop music.
- How loud (in dB) is the music where you are sitting?
- How far away should you ask to move if you want the music to be 60 dB at your new table?
- Right as the singer holds an unnecessarily high note with a frequency of 2000 Hz, the speaker glitches out and starts skipping so that the note plays over and over again. If the speed of sound in the diner is 330 m/s, what is the wavelength of her note?
- As you are driving away from the diner at 12 m/s, you can still hear the speaker playing the note in the distance. Assuming the speed of sound is same outside, what frequency do you hear as you drive away?
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