Aim: What are graphs?

Do Now: Answer the following questions in your notebook.

•Why is it important for scientists to organize their data?

•List as many ways as you can that scientists organize information visually.

A graph is a way in which to visually show information. Graphs allow for easy

comparison of multiple variables.

Graphs are constructed from data table.

A data table must include headings, units, and data.

I. Definitions:

II. Types of Graphs

•Line graph

•Bar graph

•Circle graph

**We will only be making line graphs**

Line graphs have two axis.

-The horizontal axis is the X axis it usually

is where the independent variable

is graphed

- The vertical axis is the Y axis it usually is where the dependent variable is graphed

III. Graph Parts

• EVERY graph needs a title.

The Independent Variable: is the variable that can be controlled by the experimenter (x-

axis).

It usually includes:

• time (dates, minutes, hours),

•depth (feet, meters),

•temperature (Celsius).

III. Graph Parts continued:

The Dependent Variable: is the variable that is directly affected by the independent

variable (y-axis).

It is the result of what happens because of the independent variable.

Example:

•How many inches something grew,

•Number of oxygen bubbles produced,

•How fast something happened

III. Graph Parts continued:

Direct relationship- as x gets bigger, y gets bigger. For example, the relation ship between age and

size (until maturity) is a direct relationship.

Indirect / Inverse- as x gets bigger, y gets smaller. For example, the relationship between time spent at the mall and the amount of money in your pocket is an inverse relationship.

Cyclic- a repeating pattern.

IV. Graphing Relationships

DirectIndirect /

InverseCyclic

DirectIndirect /

Inverse

Cyclic

Most relationships in Earth Science are cyclic.

•the repeating high and low tides

•temperatures go from cold to warm each day

•temperatures go from cold to warm each year

•the phases of the moon

When done, obtain a Scaling a Graph I worksheet from the back top bin.

Scaling Overview

AIM: How do you scale a graph?

When you graph, make sure you:

• Have a proper title that describes the graph

• Plan out your scaled axis before actually writing them

• Label the x-axis and y-axis appropriately

• One box along the x- axis is equal in length to one box along the y-axis.

• The two axes can be scaled differently.

Days

Rate of Change• The rate of change measures the amount of

change taking place in a given amount of time.

• This equation is found on page 1 of the Earth Science Reference Tables:

• Rate of Change = Change in Field Value

Change in Time

• Field value = what was being measured

• Change in time = the amount of time it took for the change to occur

Rate of Change = Change in Field Value Change in Time

Example Problem

• Example: The temperature in a greenhouse is 10 degrees C at 12:00 a.m. At 3:00 a.m., the temperature is 5 degrees C.

• At what rate did the temperature change?

• There is a 5 degree C change in 3hrs. (5 degrees C / 3 hrs)

Rate of change = 1.7 degrees C/hr.

Do now:

- Take out your scaling a graph I and II.

- I will be coming around to check scaling a graph II.

- From your Scaling a graph I worksheet, find the rate of temperature change from January to July

Rate of Change = Change in Field ValueChange in Time

Rate of Change = Change in Field Value Change in Time

From your Scaling a graph II worksheet, find the rate of temperature change from July to December.

Rate of Change = Change in Field ValueChange in Time