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Sara jumped off her row boat into the lake. As she pushed her body forward, the boat moved backwards. Which of Newton’s laws BEST describes the motion of Sara and her boat?
Detailed Explanation
The motion of Sara and her boat is best described by Newton's third law of motion. Newton's third law of motion states that for every action, there is an equal and opposite reaction.
When Sara pushed off the boat, she exerted a force on the boat. The boat, in turn, exerted an equal and opposite force on Sara, which caused her to move forward.
The force that Sara exerted on the boat is called the action force. The force that the boat exerted on Sara is called the reaction force.
The action force and the reaction force are equal in magnitude, but they are opposite in direction. This is why Sara moved forward and the boat moved backward.
Newton's third law of motion is also known as the law of conservation of momentum. Momentum is the product of mass and velocity. In this case, the momentum of Sara and the boat was conserved. The total momentum of Sara and the boat was the same before and after Sara jumped off the boat.
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