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Homework Help: Momentum question involving vectors

  1. Jan 17, 2010 #1
    1. The problem statement, all variables and given/known data

    What impulse is needed to change the velocity of a 90.0 kg football player from 3.6 m/s towards the north and make it 1.2 m/s toward the northeast? In what direction must the force be exerted?

    2. Relevant equations


    3. The attempt at a solution

    I drew vectors of the two momentums and found the resultant momentum to be 410N.s @ 11 E of N
    but the answer in the back of the book is 259N.s 17 E of S
    I can't think of any other way to approach this problem...
  2. jcsd
  3. Jan 17, 2010 #2

    Andrew Mason

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    Science Advisor
    Homework Helper

    This is a vector subtraction problem. The vector you are trying to find is the difference between the two given vectors.

    What momentum vector added to the football player's momentum vector (90kg x 3.6 m/s N) gives the resultant momentum vector (ie. 90kg x 1.2 m/s N45oE)?

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