Two cars are on the same straight road. Car A moves east at 63 mph and sounds its horn at 638 Hz. Determine the frequency observed by Car B's driver in each of the following cases (sketch every instance showing positions of the cars and the velocities). (a) Car B is moving east at 78 mph and is behind car A.
(b) Car B is moving east at 78 mph and is in front of car A.
(c) Car B is moving west at 78 mph and is behind car A.
(d) Car B is moving west at 78 mph and is in front of car A.

6:20 Two cars are on the same straight road. Car A moves east at 55 mph and sounds its horn at 625 Hz. Rank from highest to lowest the frequency observed by Car B's driver in each of the following cases. (Use the following as necessary: a, b, c, and d. Use only->" or .=" symbols. Do not include any parentheses around the letters or symbols. Let "behind" mean car B is west of car A, and "in front of mean car B is east of car A.) (a) Car B is moving east at 70 mph and is behind car A (b) Car B is moving east at 70 mph and is in front of car A (c) Car B is moving west at 70 mph and is behind car A (d) Car B is moving west at 70 mph and is in front of car A. Need Help? Why does a vibrating guitar string sound louder when placed on the instrument than it would if allowed to vibrate in the air while off the This answer has not been graded yet A soft drink bottle resonates as air is blown across its top. What happens to the resonant frequency as the level of fluid in the bottle decreases? This answer has notl been graded yet An airplane mechanic notices that the sound from a twin-engine aircraft varies rapidly in loudness when both engines are running. What could be causing this variation from loud to soft

v=ir = 3x15 =45 v