1a. A plane has a motor that emits a 1500Hz tone as heard to the pilot. The plane flies at 240 m/s at a crowd. What frequency does the crowd hear as the plane approaches?

 

1b. As it is in front of them?

 

1c. As it goes away?

 

  1. Did you know that there is a "best" length for a car radio antenna? Well, there is. It should be a multiple of the station's wavelength you are listening to. The problem is that this is often too long, so a substitute is to have an antenna exactly 1/4 of that length. To make a long question short here goes: If I love 97.3MHz, how long should my quarter wave antenna be?

    2.  

    3. A string is vibrating in its 3rd harmonic. F=100Hz, mL=.02Kg/m Tnesion=25N

    How long is this string?

     

  2. A student on some other planet stands over a very long pipe full of water. They perform a tuning fork lab and hear a strong tone 5 times. On the 5th time, they measure that the air column is 4m tall. They are using a 500Hz tuning fork. What is the speed of sound on this planet?

 

4. If you hear an intensity of "1 at 1m, what intensity would you hear at 3m?