Module 1—Motion
Lesson Summary
In this lesson and related lab activities you explored the following questions:
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What is a vector?
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How is a vector different than a number?
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How can you represent vectors?
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How can you communicate the direction of a vector?
A vector quantity is a measurement that has both magnitude and direction. Direction is the essential characteristic of a vector quantity that makes it different from a number. Vector quantities (such as position, displacement, and velocity) can be graphically represented using an arrow. The length of the arrow represents the magnitude (amount) of the quantity. The direction of the vector can be described using a sign convention if the vector lies along a single straight line. If the vector is not restricted to a straight line, then the navigator method or the Cartesian method could be used.
Lesson Glossary
Cartesian method: a system for measuring directions using the x-axis and y-axis
direction: the course that an object follows
displacement: a change in position including both magnitude and direction
distance: the length of the path taken to move from one place to another
navigator method: a system for measuring directions using compass bearings
position: the straight-line distance and direction of an object from the origin
scalar quantity: a measurement that has only magnitude
sign convention: a system for designating directions along a straight line; one direction is positive and the other is negative
vector quantity: a measurement that has a magnitude and a direction