An airplane moving horizontally at 150 m/s drops a package from an altitude is 490 m. How long does it take the package to reach the ground? How far, horizontally, from the spot over which it was dropped
does the package land?

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

How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects

What is the coefficient of kinetic friction μk between the block and the tabletop?