1. An airplane is traveling at 30 % of the speed of sound emits a note of frequency 8.0 kHz. At what frequency does a stationary listener hear the sound
(a) When the plane is approaching?
(b) After the plane passes? Take the speed of sound in air as 340 m/s.
2. A 500-g block is released from rest and slides down a frictionless track that begins 2.00 m above the horizontal. At the bottom of the track, where the surface is horizontal, the block strikes and sticks to a light spring with a spring constant of 35 N/m.
a. What is the velocity of the mass just before it strikes the spring
b. Find the maximum distance the spring is compressed.