An automatic focus camera is able to focus on objects by use of an ultrasonic sound wave. The camera sends out sound waves that reflect off distant objects and return to the camera. A sensor detects the time it takes for the waves to return and then determines the distance an object is from the camera.

1. If a sound wave returns to the camera 0.115 seconds after leaving the camera, how far away is the object?

There is a thunderstorm and a lightning strike some distance from your home. The light reaches you nearly immediately, yet the thunder is heard 3.5 seconds later.

1. How far away is your home from the lightning strike?

1. How long did it take for the light to reach your eyes?

An automobile is traveling away from Jack and towards Jill at 18 m/s. The horn is honking, producing a sound wavelength of 0.56 m.

1. What is the actual frequency of the sound wave?

1. What is the perceived frequency that Jack hears?

1. What is the frequency that Jill hears?

1. Who hears a higher pitch and who hears a lower pitch?