please help me with those questions

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V Part A A stationary police car emits a sound of frequency 1230 Hz that bounces off of a car on the highway and returns with a frequency Was the moving car moving towards or away from the police car? of 1275 Hz. The police car is right next to the highway, so the moving car is traveling directly toward or away from it. It's was moving towards the police car. For related problem-solving tips and strategies, you may want to view a Video Tutor Solution of Doppler effect ili: a moving listener. O It's was moving away from the police car. Submit Previous Answers V Correct Since the frequency is increased the moving car must be approaching the police car. Part B How fast was the moving car going? Express your answer in meters per second. IVO AEQ ? V = m/s Submit Previous Answers Request Answer X Incorrect; Try Again; 5 attempts remainingV Part A A swimming duck paddles the water with its feet once per time interval of 1.4 s, producing surface waves with this period. The duck is moving at constant speed in a pond where the speed of What is the duck's speed? surface waves is 0.39 m /s, and the crests of the waves ahead of Express your answer in meters per second. the duck have a spacing of 0.15 m. For related problem-solving tips and strategies, you may want to VO ? view a Video Tutor Solution of Doppler effect i: wavelengths. V m/s Submit Previous Answers Request Answer X Incorrect; Try Again; 3 attempts remaining Part B How far apart are the crests behind the duck? Express your answer in meters. DA AEd m d =V Part A Two guitarists attempt to play the same note of wavelength 6.50 cm at the same time, but one of the instruments is slightly out of tune and plays a note of wavelength 6.53 cm instead. What is the frequency of the beats these musicians hear when they play together? Express your answer with the appropriate units. HA ? fbeat = 13.21 HZ Submit Previous Answers Request AnswerPart A An oscillator vibrating at 1290 Hz produces a sound wave that travels through an ideal gas at 325 m/s when the gas What should the gas temperature be to achieve this wavelength? temperature is 22.0 C. For a certain experiment, you need to have the same oscillator produce sound of wavelength 28.3 cm Express your answer Celsius degrees. in this gas. For related problem-solving tips and strategies, you may want to AED ? view a Video Tutor Solution of Speed of sound in air. T = . C