1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Apparent frequncy of sound heard?

  1. Aug 10, 2014 #1
    1. The problem statement, all variables and given/known data

    A car is moving in a straight line at 30m/s approaches a stationary source which emits sound of frequency 5000hz. If the speed of sound is 330m/s . The apparent frequncy received by car is ((330+30)/ 330) x 5000= 5455hz.
    What 's the frequency reflected form the car? the ans given is 6001hz.

    why not the frequency received by the car = frequency of sound reflected by the car? which means the apparent frequency reflected form the car is also = 5455hz?

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Aug 10, 2014 #2


    User Avatar
    Science Advisor

    The reflected sound is at the frequency you say, but only when "heard" from the car. The car itself is a source moving with respect to the medium, in the direction of the emitted (reflected) sound.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted