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reference point

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

International System of units (SI)

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


the state in which one objects distance from another is changing

When is an object in motion?

If it changes position relative to a reference point


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


one hundreth of a meter.


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

constant speed

the speed of an object does not change

How do you calculate average speed

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


speed in a given direction

How can you show motion of an object?

On a line graph where you plot distance against time.

What is shown on the x axis of the graph?


What is shown on the y axis of graph ?


What does a straight line represent on the graph?

motion at a constant speed

What does a horizontal line on the graph represent?

An object that is not moving at all

The faster the motion

The steeper the slope on the graph.

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