1. Chapter 4-2 Graphs of Motion The Foundations of Physical Science

2. What does this mean?
“A PICTURE IS WORTH A THOUSAND WORDS”

3. Graphs of Motion
A graph is a special picture that can quickly give meaning to a lot of data (numbers)
You can easily spot relationships on a graph
It is much more difficult to spot relationships by looking at columns of numbers

5. Position VS Time Graph
Constant speed is speed that stays the same and does not change
To graph this data, you put position on the vertical (y) axis and time on the horizontal (x) axis
An object moving at constant speed ALWAYS creates a STRAIGHT LINE on the position vs time graph

7. Graphs of Motion
You can use position vs. time graphs to compare the motion of different objects.
The steeper line on a position vs. time graph means a faster speed.

8. Graphs Show Relationships
The relationship between variables may be strong, weak, or there may be no relationship at all
In strong relationships, large changes in one variable make similarly large changes in the other variable

9. Graphs Show Relationships
In the weak relationship, large changes in one variable cause only small changes in the other
When there is no relationship, the graph looks like scattered dots

10. SLOPE You can use position vs time graphs to quickly compare speeds
A STEEPER line on a position vs time graph means a FASTER speed
The “steepness” of the line is called its slope
SLOPE is the ratio of the rise (vertical change) divided by the run (horizontal change) of a line on a graph

12. Graphs of changing motion
Objects rarely move at the same speed for a long period of time.
A speed vs. time graph is also useful for showing the motion of an object that is speeding up or slowing down.

13. Speed VS Time Graphs
The speed vs time graph has speed on the y axis and time on the x axis
This graph can also be used to find the distance that an object has traveled