Results 1 to 2 of 2

Math Help - vectors

  1. #1
    Member
    Joined
    Nov 2009
    Posts
    107

    vectors

    At one instant ,ships X and y are at a distance of d from each other.THe velocities of ship x and ship y are u and v respectively. Angle a and b are acute. Find the tangent of angle betweeen the direction of relative velocity and \vec{xy}

    My work:

    the relative velocity vector is

    xVy=Vx-Vy=(u+vsin(a+b))i+(-v cosb)j

    relative displacement vector, xRy=(-d)i

    Before i proceed with the dot product formulas, can i confirm whether the above is crrect?
    Attached Thumbnails Attached Thumbnails vectors-vectors-diagram.jpg  
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Dec 2009
    From
    1111
    Posts
    872
    Thanks
    3
    Quote Originally Posted by hooke View Post
    At one instant ,ships X and y are at a distance of d from each other.THe velocities of ship x and ship y are u and v respectively. Angle a and b are acute. Find the tangent of angle betweeen the direction of relative velocity and \vec{xy}

    My work:

    the relative velocity vector is

    xVy=Vx-Vy=(u+vsin(a+b))i+(-v cosb)j

    relative displacement vector, xRy=(-d)i

    Before i proceed with the dot product formulas, can i confirm whether the above is crrect?
    Dear hooke,

    Your expressions are incorrect.

    According to your figure,

    Velocity of x relative to y=velocity of x relative to earth-velocity of y relative to earth= u\underline{i}-(-v\cos{(a+b)}\underline{i}+v\sin{(a+b)}\underline{j  })

    Displacement of x relative to y = (-d\cos{a})\underline{i}+(d\sin{a})\underline{j}

    Hope this helps.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: November 15th 2011, 05:10 PM
  2. Replies: 3
    Last Post: June 30th 2011, 08:05 PM
  3. Replies: 2
    Last Post: June 18th 2011, 10:31 AM
  4. [SOLVED] Vectors: Finding coefficients to scalars with given vectors.
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: January 23rd 2011, 12:47 AM
  5. Replies: 4
    Last Post: May 10th 2009, 06:03 PM

Search Tags


/mathhelpforum @mathhelpforum