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2-D Uniform Motion Problem

  1. Mar 28, 2012 #1
    A fishing boat leaves port at 04:30 h in search of the day's catch. The boat travels 4.50km[E], then 2.50km, and finally 1.50km[W] before discovering a large school of fish on the sonar screen at 06:30h.

    a) What is the boat's average speed.
    b) Calculate the boat's average velocity.

    Solved a) by finding the total distance (8.5Km) and dividing it by the total time(2h).
    I got 4.25km/h for my a). Which I have solved.

    Don't understand b) at all.. Please help the answer is 1.95km/h[S50E]
  2. jcsd
  3. Mar 28, 2012 #2
    Try vector addition. Set up your coordinates so that the x axis corresponds to east-west and the y axis corresponds to north-south and have the boat start at the origin.
  4. Mar 28, 2012 #3
    I think you have to understand what is speed and velocity thus you have to know what is scalar and vector.

    Different set of mathematical rules apply to scalar and vector example addition.
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