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Homework Help: Kinematics question

  1. Apr 19, 2005 #1
    i have a question here about kinematics.

    1. When a aircraft is 4000m above the ground and flying upwards with a velocity of 50 ms-¹ at an angle of 30º to the horizontal. A bomb is released.Neglecting air resistance, calculate

    (a)the time taken by the bomb to reach the ground,
    (b)the velocity of the bomb when it strikes the ground.(g=10 ms-²)

    (a)h=4000m
    vertical component of velocity=25.5
    horizontal component of velocity=43.3

    s=ut+1/2at²
    4000=0+5t²
    t=28.5

    v=u+at
    25=0+10t
    t=2.5

    t=28.5+2.5
    t=31
    is it correct?

    (b)vertical component of velocity=25.5

    v=u+at
    =0+10(28.5)
    =285 ms-¹

    vertical component of velocity=285 ms-¹-25.5 ms-¹=259.5 ms-¹

    velocity of bomb, v=(259.5²+43.3²)½
    =263 ms-¹

    plz someone check the answer 4 me.TQ!
     
  2. jcsd
  3. Apr 19, 2005 #2
    Edit: Sorry I misinterpeted your work. Everything looks in order.
     
    Last edited: Apr 19, 2005
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