A submarine moves away from an undersea vertical cliff at aspeed vs = 10.0 m/s. It emits a sound wave at afrequency fe = 20,000. Hz, which travels to thecliff and reflects off it at a frequency fr.The reflected wave travels back to the submarine and generatesbeats with the emitted wave ( fe ) that aredetected by the sub’s sensors. For a speed of sound in seawaterv = 1,174 m/s, the frequency of the beats are (Enter youranswer in units of Hz. Only enter the number using3 significant figures.
