Name: ______________________

Quiz 1

09/19/2005

Ch. 16-17

The speed of sound in air is 344 m/s. The speed of sound in seawater is 1500 m/s.

1) You are underwater and see a ship explode. 4.4s later you hear the explosion and immediately come to the surface. How much longer (from the time you heard the explosion underwater) will it be before you hear the explosion in the air above the water? You may ignore the time it takes for the light from the explosion to reach your eyes.

2) A woman stands 3.2m from speaker A. What is the closest distance to the woman that speaker B can be placed so that a 440Hz sound will constructively interfere at the woman's position if speakers A and B are out-of-phase?

3) The formula for the Doppler shift is:

If the source is going toward the observer and the observer is going toward the source, what is the numerator sign?

a) +

b) -

What is the denominator sign?

a) +

b) -