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Homework Help: Impulse and Momentum, 2 dimension

  1. Oct 4, 2011 #1
    Been stuck on this question for days and any help would be greatly appreciated

    A baseball going horizontally at 32.0 m/s [E] with a mass of 0.152 kg is hit by a bat for 0.002 seconds. the velocity after the ball after contact is 52.0 m/s [W 20 N]

    Find the impulse experienced by the ball. (I'm guessing total impulse, first vector and the other)

    pretty much what i have to work with is F net Δt = m(v2-v1)


    Tutors keep telling me I'm wrong without pointing me in the right direction just adding more confusion. here is what i did. ...

    V1 being its initial vector

    v1x = 32cos0 = 32
    v1y = 32sin0 = 0

    V2 being after collision

    v2x = -52cos20 = -48.864
    v2y = 52sin20 = 17.785

    now applying Fnet Δt = m(v2-v1) for x and y components.

    fnetx Δt = m(-80.864)
    fnetx(0.002)=0.152(-80.864)
    fnetx = -6145.664

    then same stuff for y

    fnety =1351.664

    after that i use both values to plug into a triangle then Pythagorean to find unknown side which to me seems like it would be the impulse of the ball. which i got 6292.5 kg m/s.

    I need help with this, I just can't seem to rack my brain around what is wrong. Things I'm pretty sure I need to use is the fnet Δt=m(v2-v1) and some kind of triangle.

    Thanks a lot in advance guys.
     
  2. jcsd
  3. Oct 4, 2011 #2
    heres what i did
     

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