The acoustic field in a standing wave tube is given by aexp(ia-ikx)+bexp(iar tikx) where the incident wave has an amplitude of a=10 pa. the fluid in the tube is air and at the end of the tube there is an interface with a fluid that has a characteristic impedance of pc-560 rayls. what is the magnitude of the reflected wave b, and what is the difference in level between the reflected wave and the incident wave in db?

When the velocity of an object is doubled, by what factor is its momentum changed? by what factor is its kinetic energy changed? a) the momentum is zero. b) the momentum is not zero. c) difficult to say.

Ajet plane has a sound level of 120 db at a distance of 60 m. what is the q23. sound level at a distance of 6.0 km? (60)2 (6000)? om solution 80db db, hint: 16x assume ultrasound waves travel through the body of an animal at 1540 q24. m/s. if a 30,000 hz signal were reflected off a portion of a heart which was moving toward the source at 3 m/s, what frequency signal would return to the stationary source? solution 30.117hz

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.