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: Relative Speed

  1. Jan 25, 2010 #1
    1. The problem statement, all variables and given/known data

    A ship cruises forward at vs = 4 m/s relative
    to the water. On deck, aman walks diagonally
    toward the bow such that his path forms an
    angle θ = 30◦ with a line perpendicular to
    the boat’s direction of motion. He walks at
    vm = 5 m/s relative to the boat.
    Here's a picture.
    http://up.arb-up.com/i/00113/v5wq5xx2uodk.jpg [Broken]


    2. Relevant equations
    I'm not sure, I didn't use any equations. I solved it by breaking the velocity into vector compeonents.


    3. The attempt at a solution
    I do the sin of 30 and multiply that by the man's velocity on the ship 5m/s , which would give an x velocity, or his velocity relative to the water, of 2.5m/s. Then, I add the speed of the ship to his velocity which gives me 6.5m/s, but my answer is not correct. What is wrong with my process
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted