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Newton's Laws of Motion

  1. Oct 26, 2014 #1
    1. The problem statement, all variables and given/known data
    A truck (1200kg) is travelling south at 22m/s
    a) what is the net force required to bring the truck to a stop in 330m?
    b) what is the cause of this net force? (im assuming the answer is friction due to brakes)

    Mass= 1200kg (1.2*10^4)
    Velocity= 22m/s [south]
    What force is required to stop the object (1200kg) in 330 meters?

    2. Relevant equations

    anything needed to solve the equation?

    3. The attempt at a solution

    ΣF= m*a
    =1200kg * a

    a= ( 22 m/s [south] ) / Δt

    330m/22m= Δt
    t=15 seconds

    a= 22/15
    a = 1.4666667

    "a" is now the number of meters per second required to decelerate to reach fnet = 0 ?

    Unsure if this is on the right track or extremely off what I need to do for a question like this
    Last edited: Oct 26, 2014
  2. jcsd
  3. Oct 26, 2014 #2

    rude man

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    (a) Think energy conservation. Kinetic energy change to heat.
    (b) you're right.
  4. Oct 26, 2014 #3


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    OK up to here.

    ##x = vt## only works when there's no acceleration.

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