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Direction: Solve the following word problems. Show your complete solution and answer. 1. A police car's siren emits a sinusoidal wave with frequency of 300 Hz. The speed of sound is 340 m/s and the air is still. a.) If a listener is at rest and the siren is moving away at 30 m/s, what frequency does the listener hear? b.) If the siren is at rest and the listener is moving away from it at 30 m/s, what frequency does the listener hear? 2. The siren is moving away from the listener with a speed of 45 m/s relative to the air, and the listener is moving toward the siren with a speed of 15 m/s relative to the air. If the siren is emitting a 1kHz sound, what frequency does the listener hear? 3. What is the frequency heard by a person driving at 15 m/s toward a factory whistle that is blowing at a frequency of 800 Hz? Assume that the speed of sound is 340 m/ s. 4. A truck and an ambulance move at the same rate of 13 m/s toward each other but on different lanes. If the ambulance siren emits sound of frequency 1200 Hz, what is the frequency of the sound that the truck driver hears? 5. The police car is moving toward a warehouse at 30 m/s. If the police car is emitting a 1kHz sound, what frequency does the driver hear reected from the warehouse? Assume that the speed of sound is 340 m/s. Direction: Explain and elaborate your answer on the following question. Apply the information you have learned on this module. Minimum of fifty (100) words per queson. 1. What is the importance of safety equipment such as ear protectors for workers in loud environments (e.g. those who use jack hammers or direct aero planes to their parking bays)? 2. A sound source and a listener are both at rest on the earth, but a strong wind is blowing from the source toward the listener. Is there a Doppler effect? Why or why not