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Please Help me with these Vector problems?

  1. Dec 5, 2007 #1
    Please help me...thank you so much!

    1.) Katie pushes on a cow with a force of 200 N while John pulls on the cow with a force of 250 N. If the cow pushes back with a force of 325 N, what is the resultant force vector?

    2.) Amanda is riding her flying cow towards north wth a velolcity of 280 m/s. If the wind blows from the west at 50 m/s, what is her resulant vector?

    3.) If Alex pulls a cow with a force of 890. N with a rope that is 25 degrees to the horizontal, what are the X and Y components of the force exerted by Alex?

    4.) A cow jumps off a diving board witha velocity of 9.5 m/s at a vertical angle of 22 degrees to the vertical. What are the X and Y components of the velocity?

    5.) Bob pulls a cow in a wagon with a force of 55 N at an angle of 38 degrees to the horizontal. What are the X and Y components of the force?
  2. jcsd
  3. Dec 5, 2007 #2
    You know, we can't do your homework for you. You have to show some work first.
  4. Dec 5, 2007 #3
    Is the force that Katie exerts on the cow along the same line of action as John's force?
    Does both John's and Katie's forces act through the center of mass of the cow?
    Finally, all depends on what direction is the cow trying go in?
  5. Dec 5, 2007 #4
    I'm not sure what formula I should use for this, how do I go about doing it?

    The cow is going to the right. John and Katie are going to the left.
  6. Dec 5, 2007 #5


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    Gold Member

    There is no formula, in physics using formula is meaningless if you can't other stand the what is actually going on, here all you have to do (yes all!) is draw arrows showing which way each force is acting, add all the +ve (e.g force to the right) directions and the -ve (forces to the left) directions and see what you get. . .
  7. Dec 5, 2007 #6
    The "resultant force" of a force system depends entirely on the directions of the all the forces. If John was pulling to the east and Katie was pushing towards the south while the cow was "pushing" to go southwesterly an entirely different answer would be than mentioned above.

    If the lines of action did not pass through the center of mass of the cow, then the cow might have a tendency to spin...
  8. Dec 5, 2007 #7
    Oh okay I see, so the proximate vicinity the cow could be in could that be calculated from the adding together of the two forces against it (200 and 250) and subtract that from the cow's force to get that the direction that the cow is going in is 125 to the right maybe?
  9. Dec 5, 2007 #8
    Correct. 125 to the right...
  10. Dec 5, 2007 #9

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