Q 1. The highest musical note on a piano has a frequency of 4,286 Hz. Why would a tape of piano music sound terrible if played on a tape player that reproduces frequencies only up to 5,000 Hz?
2. A steel cable with a total length 30 m and mass 100 kg is connected to two poles. The tension in the cable is 3,000 N, and the wind makes the cable vibrate with the frequency of 2 Hz. compute the wavelength of resulting wave on the cable.
3. A 1,750 Hz pure tone is played on a stereo in an open field. A person stands at a point that is 4 m from one of the speakers and 4.5 m from the other. Does the person hear tone? Clarify.
4. Ultrasound probes can resolve structural details with sizes approximately equal to the wavelength of an ultrasound waves themselves. What is a size of the smallest feature observable in human tissue while examined with 25 MHz ultrasound? The speed of sound in human tissue is 1,640 m/s.
5. Ultrasound can be used to measure the thickness of protective coatings applied to surfaces as part of industrial processes since it reflects well from boundaries separating regions with different densities. How thick is the layer of plastic coating on a metal substrate that produces ultrasound echoes from upper and lower surfaces having round-trip times that differ by 0.77 us. Assume the speed of sound in the plastic is 800 m/s.
6. A person stands at a point 400 m in front of the face of a sheer cliff, if the person shouts, how much time would elapse before an echo is heard?
7. A 78 kg man drops from rest on a diving board -3.5m above the surface of the water and comes to rest .59 s after reaching the water. What force does water exert on the man? Answer in units of N
8. What are the frequencies of first four harmonics of middle C (261.6Hz)?