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Homework Help: Relative velocity of a boat

  1. May 12, 2008 #1


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    1. The problem statement, all variables and given/known data

    2. A boat heads 15° west of north witha water speed of 3m/s. Determine its velocity relative to the ground when there is a 2m/s current from 40° east of north.

    2. Relevant equations

    cosine law

    3. The attempt at a solution

    I found the angle between the two vectors to be 125 and then used cosine law and gor the resultant velicity as 4.459 km/ h but the ans. is 2.5 m/h
  2. jcsd
  3. May 12, 2008 #2


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    Hi a.a! :smile:

    2.5 is the right answer if the current is the other way round. :confused:
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