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    so ive just started learning m2 buy my teacher is awful, shes given us a few question but i have no clue what to do

    a ball mass 0.4kg is fired horizontally 350m/s. it hits a target penetrating for 0.25m before coming to rest, using the work energy principle find the resistive force of the target
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    well you need to let the kinetic energy of the ball equal the work done against the resistance of the target

    KE = .5mv2

    work done = Force * Distance
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    (Original post by the bear)
    well you need to let the kinetic energy of the ball equal the work done against the resistance of the target

    KE = .5mv2

    work done = Force * Distance

    how do i get the force of this? 'f=ma' i dont know acceleration

    edit
    do i do 245000=f x 0.25
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    (Original post by printergirl)
    edit
    do i do 245000=f x 0.25
    yes
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    (Original post by TenOfThem)
    yes
    so answer is 98000 N, this seems very large!
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    (Original post by printergirl)
    so answer is 98000 N, this seems very large!
    Well

    It was going very fast

    And it did have to stop pretty quickly

    So a big force would be needed
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    350 m/s is 790 miles per hour....

    Jumbo Jets cruise at 250 m/s

    none of the Fighter Planes in WWII exceeded 690 miles per hour:

    http://www.militaryfactory.com/aircr...d-by-speed.asp
 
 
 
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