# ps11c30 - Ph 111.01 November 14, 2008 PS 11c (30) Problem...

This preview shows pages 1–2. Sign up to view the full content.

Ph 111.01 November 14, 2008 PS 11c (30) Problem 1. Suppose you are stopped in your car at a traffic light, and an ambulance approaches you from behind with a speed of 14 m/s. The siren on an ambulance produces sound with a frequency of 800 Hz. What frequency will you hear? Hz Solution. The observed frequency f ' is given in terms of the source frequency f by () 11 800 Hz 834 Hz 14 m/s 1 1 343 m/s ff u v == = Problem 2. A police car emitting a siren wail ( 450 Hz) is driving towards a fleeing suspect at v/ 35 , where v is the speed of sound. The suspect is running away at v/ 45 . a.) What frequency does the suspect hear? Hz b.) To double-check your answer: is the distance between the car and suspect increasing or decreasing? Based on this, do you expect the frequency observed to be larger or smaller than that emitted? Is this what you got in part a? Solution. (a) The frequency f 2 which would be heard by a stationary observer between the two cars is given by 21 1 450 Hz 450 Hz 463.2 Hz 1 35 35 1 uv v v = = −−

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 05/13/2010 for the course PHYSICS 111 taught by Professor Staff during the Fall '08 term at S.F. State.

### Page1 / 2

ps11c30 - Ph 111.01 November 14, 2008 PS 11c (30) Problem...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online