15. From his bedroom, Tucker can hear the distant sound of a train horn as the train travels through the mountains. The horn has a frequency of 800.0Hz as the train rolls along at 20.00 m/s. What frequency does Tucker hear as the train travels away? *       a. 685 Hz       b. 756 Hz       c. 773 Hz       d. 658 Hz       e. None of the above

You drving in car 1 and your friend is drving in car 2 playing music at a frequency f. Van V is also driving on the same road. 1) Write an equation for the frequency you will hear generated by your friend and bounced off the van. Express the frequency you heard in terms of f.  v car 1 = 100.0 km/h v car 2 = 80.00 km/h v van V = 60.00 km/h

Suppose you pluck a string on a guitar and it produces the note A at a frequency of 440 Hz. Now you press your finger down on the string against one of the frets, making this point the new end of the string. The newly shortened string has 4/5 the length of the full string. When you pluck the string, its frequency will beA. 350 Hz         B. 440 Hz        C. 490 Hz        D. 550 Hz

You stand at x = 0 m, listening to a sound that is emitted at frequency fs. as shown the frequency you hear during a four-second interval. Which of the following describes the motion of the sound source?A. It moves from left to right and passes you at t = 2 s.B. It moves from right to left and passes you at t = 2 s.C. It moves toward you but doesn’t reach you. It then reverses direction at t = 2 s.D. It moves away from you until t = 2 s. It then reverses direction and moves toward you but doesn’t reach you.