Problem 5.5: A 4-kg block sits on an 8-kg block pushed across the floor

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A 4-kg block sits on an 8-kg block that is pushed across the floor as shown (position is given in meters and time is given in seconds). Restart.

  1. Which free-body diagram is correct? Give reasons why the other three diagrams are incorrect.
  2. Draw the correct free-body diagram and label the force that causes each interaction.

Be sure to include the force of friction if two surfaces are rubbing against each other. Remember that the length of an arrow is proportional to the value of the quantity being represented, and its length does not represent the actual size of the quantity.