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Homework Help: Newton's Third Law

  1. Sep 22, 2007 #1
    1. The problem statement, all variables and given/known data

    All small compact car is giving a push to a large van that has broken down and they travel along with equal velocities and accelerations. While the car is speeding up, is the force it exerts on the van larger than, smaller than, or the same magnitude as the force the van exerts on it? Which object, the car or the van has the largest net force on it, or are the net forces the same? Explain.

    2. Relevant equations

    no equations necessary? just Newton's Third Law

    3. The attempt at a solution

    I drew the free body diagrams for this with the force car on van and force van on car, but I'm not really understanding difference between equilibrium and Newton's 3rd Law
  2. jcsd
  3. Sep 22, 2007 #2


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    Staff Emeritus
    Science Advisor

    The van is being accelerated by the force imposed by the compact car. The inertia of the van results in force back on the car.

    The car is accelerating at the same rate as the van, but the tractive force of the car (through wheels/tires) must accelerate the mass of the car and van.
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