1. Not finding help here? Sign up for a free 30min 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!

What is the speed of the waves on the lake?

  1. Sep 20, 2008 #1
    1. The problem statement, all variables and given/known data
    While anchored in the middle of a lake, you count exactly three waves hitting your boat every 12.0 s. You raise anchor and start motoring slowly in the same direction the waves are going. When traveling at 1.50 m/s, you notice that exactly two waves are hitting the boat from behind every 12.0 s.

    What is the speed of the waves on the lake?

    2. Relevant equations
    f+-=(1+-v0/v)f0


    3. The attempt at a solution

    I have messed up this kind of problem before, so there are many places for me to make mistakes.

    3 waves 12 seconds
    V= 1.5m/s
    2 waves 12 seconds

    T1 = 4s
    T2 = 6s

    f1=.25
    f2=.17

    .17=(1-v0/1.5).25

    .68=1-v0
    -.32=-v0/1.5
    .48=v0

    I know I made a mistake somewhere...
     
  2. jcsd
  3. Sep 20, 2008 #2
    Re: Waves

    You got the overall idea for the equations but you made a slight mistake...1.5 m/s is the value of Vo (the object's velocity) and v is the velocity of the wave. You mixed the two up.
     
  4. Sep 20, 2008 #3
    Re: Waves

    Thank you, that was the mistake.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: What is the speed of the waves on the lake?
Loading...