Page 37 - Science Course 2 (Book 2)

Mo8-L4: Vocabulary Review

Direction: On each line, write the term from the word bank that correctly replaces the underlined words in
each sentence.

force pair law of conservation of momentum momentum Newton’s third law of motion
1. If two objects are moving at the same speed, the object with more mass has more of a measure of how
hard it is to stop a moving object.

2. A set of forces that two objects apply to each other does not result in a net force of zero because each
force acts on a different object.

3. The transfer of momentum between two or more objects is described by the law that states that the total
momentum of a group of objects remains the same unless outside forces such as friction act on the
objects.

4. The motion that occurs when a skateboarder pushes on a wall is described by the law that states that
when one object exerts a force on a second object, the second object exerts an equal force in the opposite
direction on the f rst object.

Mo8-L4: Key Concept Organizer

Direction: Each of the following object pairs exerts forces on each other. Write A on the line next to
objects that exert the action force and write R next to objects that exert the reaction force.

1. swimmer’s hands /water

2. a starting block /a runner’s foot

3. a baseball bat /a baseball

4. water under a paddle /a paddle pushing a boat

5. a table /a cat jumping off a table

6. an arrow /a target

7. an airplane wing pushing down on air /air pushing up on a wing

8. a girl sitting in a chair /a chair supporting a girl

9. a windmill /wind

10. a pencil /a piece of paper

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