This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: homework 14 ALIBHAI, ZAHID 1 Latest unpenalized work: Apr 30 2007 Mon day 04:00 (after this date you can not make a perfect score). Work cutoff: May 2 2007, 4:00 am. Question 1 part 1 of 2 10 points An ambulance is traveling north at 49 m / s and is moving towards a car that is traveling south at 26 . 5 m / s. The ambulance driver hears his siren at a frequency of 690 Hz. The velocity of sound is 330 m / s . Ambulance 49 m / s 26 . 5 m / s Police What wavelength does the driver of the car detect from the ambulances siren? Answer in units of m. Question 2 part 2 of 2 10 points At what frequency does the driver of the car hear the ambulances siren? Answer in units of Hz. Question 3 part 1 of 2 10 points The equation for the Doppler shift of a sound wave of speed v , reaching a moving detector, is f = f parenleftbigg v v d v v s parenrightbigg , where v d is the speed of the detector, v s is the speed of the source, f is the frequency of the source, and f is the frequency at the detec tor. In the numerator the + / indicates when the detector is moving toward/away from the source. In the denominator the / + indi cates when the source is moving toward/away from the detector. A train moving toward a detector at 25 m / s blows a 350 Hz horn. The velocity of sound is v sound = 343 m / s . What frequency is detected by a stationary train? Answer in units of Hz. Question 4 part 2 of 2 10 points What frequency is detected by a train moving toward the first train at a speed of 15 . 5 m / s? Answer in units of Hz. Question 5 part 1 of 1 10 points A police car is traveling at a speed v c to the left. A truck is traveling at a speed v t to the right. A wind is blowing in the opposite direction as that of the truck with a speed v w to the left. The frequency of the siren on the police car is f c . The speed of sound in air is v a . Let v o be the speed of the observer in the truck, and v c be the speed of the source , the police car. Police v c v t Truck v w wind What is the frequency f t heard by an ob server in the moving truck? 1. f t = v a + v t v w v a + v c v w f c 2. f t = v a v t + v w v a + v c v w f c 3. f t = v a + v t + v w v a v c + v w f c 4. f t = v a + v t v w v a v c + v w f c 5. f t = v a v t v w v a + v c v w f c 6. f t = v a + v t + v w v a + v c v w f c 7. f t = v a v t v w v a v c + v w f c 8. f t = v a v t + v w v a v c + v w f c homework 14 ALIBHAI, ZAHID...
View Full
Document
 Spring '08
 Turner
 Work

Click to edit the document details