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reference point

a place or object used for comparison to determine if something is in motion

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International System of units (SI)

A system of measurement based on multiples of 10 and on established measures of mass, length and time.

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motion

the state in which one objects distance from another is changing

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When is an object in motion?

If it changes position relative to a reference point

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meter

Basic SI unit of length. It is a little longer than a yard.

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centimeter

one hundreth of a meter.

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speed

the distance an object travels in one unit of time (Distance/Time)

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constant speed

the speed of an object does not change

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How do you calculate average speed

Dvide total distancetraveled by total time. (Total distance/total time)

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Velocity

speed in a given direction

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How can you show motion of an object?

On a line graph where you plot distance against time.

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What is shown on the x axis of the graph?

time

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What is shown on the y axis of graph ?

distance

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What does a straight line represent on the graph?

motion at a constant speed

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What does a horizontal line on the graph represent?

An object that is not moving at all

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The faster the motion

The steeper the slope on the graph.

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