1. The sound a mosquito makes is produced when it beats its wings at the avg frequency of 620 wing beats per second. What is the wavelength of the sound waves produced by the mosquito?
2. You are listening to an outdoor concert on a day when the temperature is 0oC. The sound of a wavelength of 0.490m is emitted by a flute on the stage 125m from where you are standing.
a) What is the time elapsed before you hear the sound emitted from the flute? Find the speed of sound according to the temperature first
b) What is the frequency of the sound?
Mar 7­6:43 AM
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3. A short ultrasound pulse is emitted from a medical imaging device and echos are produced when the pulse is reflected at a tissue interface. The echo signals are received back at the device and then analyzed to build up an image of the organ. The speed of sound in soft tissue is 1540 m/s. If an echo is received 58.2X10­6 s after the pulse was emitted, how far is the tissue interface from the ultrasound device?
5. While fishing from a boat anchored offshore, you see another fishing boat between your boat and the shore. The other boat sounds a 510 Hz horn as it heads toward shore at a speed of 18m/s.
a) If your boat is stationary, what is the frequency of the sound waves that reach you?
b) If your boat heads out to sea at 15 m/s, what is the frequency of the horn's sounds waves you now hear?
Mar 7­6:47 AM
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6. A species of bat navigates by emitting short bursts of sound waves that have a frequency range that peaks at 58 kHz.
a) If a bat is flying at 4.0 m/s toward a stationary object, what is the frequency of the sound waves that are reaching the object?
b) What frequency of the reflected waves are detected by the bat?
c) What is the difference between the frequency of the sound waves emitted by the bat and the ones detected by the bat if the bat and the object is a moth approaching at 1.0 m/s?
Mar 7­6:57 AM
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7. Hannah places an open, vertical glass tube into a container of water so the lower end of the tube is submerged. She holds a tuning fork over the top of the tube while adjusting the water level in the tube. Hannah hears the loudest sound when the tube has 32.7 cm of air in it and again when it has 98.2 cm. What is the frequency of the tuning fork?
Mar 7­7:01 AM
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