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Homework Help: Relative Velocity Expression

  1. Sep 28, 2010 #1
    Ship A is located 3.3 km north and 2.7 km east of ship B. Ship A has a velocity of 22 km/h toward the south and ship B has a velocity of 40 km/h in a direction 37° north of east.

    (a) What is the velocity of A relative to B?

    (b) Write an expression for the position of A relative to B as a function of t, where t = 0 when the ships are in the positions described as above.

    (c) At what time is the separation between the ships least?

    (d) What is that least separation?


    2. Relevant equations: Vaw = Vab + Vbw

    3. Okay, so I got the answer for part a, which is -31.95i - 46.07j, but I'm completely lost on the rest of the parts. I have no idea on how to express b in terms of i and j, let alone solve for it, any ideas?
     
  2. jcsd
  3. Sep 28, 2010 #2
    Okay, so I figured out part b, but how can I go about doing part c?
     
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