Focus Questions

1-1  What makes things move?

1-2 How does friction affect the force needed to move an object?

1-3 How do multiple forces affect motion?

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Vocabulary

energy        force       friction        interaction         kinetic energy        net force

Newton        spring scale

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Concepts

• a force is a push or pull

• the metric unit for force is the newton (N)

• friction is a force that acts to oppose a force acting to put a mass in motion

• net force is the sum of the forces acting on a mass