Newton's third law of motion

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  1. Introduction to Newton's third law
  2. What is Newton's third law?
  3. Identifying forces in action-reaction force pair
  1. Understanding Newton's third law and free body diagrams

    A rock sits on a table. Draw complete free body diagrams for the rock and the table and highlight the action-reaction pair that includes the rock pushing down on the table.

    1. Calculations with Newton's second and third laws
      1. An 85.0 kg fireman slides down a pole with an acceleration of 2.85 m/s2m/s^{2}. Find the action-reaction force pair that involves the pole and calculate these forces.
      2. Two ice skaters stand on a frictionless ice rink and face each other, each holding the end of a rope. 50.0 kg skater A pulls on the rope, pulling 40.0 kg skater B with a force of 25.0 N.

        i. Draw a free body diagram and find the acceleration of skater B.

        ii. When skater A pulls on skater B, does skater A accelerate? If so, draw a free body diagram and calculate the acceleration.