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Homework Help: Forces Help!

  1. Sep 9, 2005 #1
    Katie, who is traveling southward in her bumper car, aims her car toward Sam, who is traveling northward in his bumper car. The cars collide and briefly come to a stop.

    What is the direction of the force exerted on Katie's car during the collision?

    What can you say about the magnitude of the force that Katies's car exerts on Sam's car versus the magnitude of the force that Sam's car exerts on Katie's car?

    What is the direction of the acceleration of Katie's car during the collision?

  2. jcsd
  3. Sep 9, 2005 #2


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    What have you done on this? It's hard to offer comments or hints without knowing what you understand about these problems.
  4. Sep 9, 2005 #3
    Well, both cars collide headon with each other, and completely stop moving straight after the collision.

    The force needed to stop Katies car will be in the opposite direction of motion, so since she is moving southwards, the force on the car must be northwards.

    When working with forces, which are vectors, you have to take their direction into account. So if two forces opposed each other (the collision), one force must be positive, and the other must be negative.
    They said that the two cars stop moving after the collions, therefore the forces that the cars exert on each other must be the same but in opposite directions (e.g. the resultant force will be 0 because the cars stop moving).

    Katies car collides headon with Sams car, so Katie car must be accelerating in the opposite direction of the intitial motion (e.g. she is decellerating).

    Hope that helped, forgive me if I am wrong.
  5. Sep 10, 2005 #4
    Thank you to those who replied... its greatly appreciated!
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