2485

Physics Waves And Oscillations Level: High School

Doppler Effect

A French submarine and a U.S . submarine move toward each other during maneuvers in motionless water in the North Atlantic . The French sub moves at 50.0 km/h and the U.S. sub at 70.0 km/h . The French sub sends out a sonar signal (sound wave in water) at 1000 Hz . Sonar wave travel at 5470 km/h .

a) What is the signal’s frequency as detected by the U.S. sub ?

b) What is the frequency detected by the French sub in the signal reflected back to it by the U.S. sub ?