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In: Physics

You and a friend drag a 28.8 kg fallen tree branch across a level field. You...

You and a friend drag a 28.8 kg fallen tree branch across a level field. You pull with a force of 135.0 N at an angle of 25.0º above the horizontal while a friend’s pull force is parallel to the ground, the kinetic coefficient of friction between the branch and the ground is µk=0.825 and the static coefficient of friction is µs=0.925. The branch starts from rest and is dragged 20.0 m in 15.0 s.

  1. What is the acceleration of the branch?
  2. What is the magnitude of the normal force acting on the branch?
  3. What is the magnitude of your friend’s pull force?
  4. If you and your friend were to stop pulling and then your friend leaves, would you be abele to get the branch moving again with the same force? If yes, prove it, if not, what force is needed to start the branch moving?

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