Independent Variables
Dependent Variables
Control Variables (Constants)
Coordinate Planes/Graphs
Graphing
100
What is the independent variable?
The variable that is changed or controlled in a scientific experiment to test the effects on the dependent variable.
100
What is the Dependent Variable?
The variable being tested and measured in a scientific experiment.
100
What is a control variable?
The experimental element which is constant and unchanged throughout the course of the investigation.
100
On a coordinate plane, the axis going left and right is the ____ axis and the axis going up and down is the _____ axis.
On a coordinate plane, the axis going left and right is the X axis and the axis going up and down is the Y axis.
100
Using the coordinate plane on the floor or on the board, graph (3, 5).
Correctly graphed?
200
The time it takes to run a mile, depends on the time of day it is run. What is the Independent Variable?
Time of day.
200
Does the height you drop a ball from affect the height it will bounce?
What is the dependent variable in this experiment?
The height the ball bounces.
200
. You are managing a large feed lot of cattle. A pharmaceutical company wants you to try a new antibiotic to treat shipping fever in newly arrived cattle. You are currently not using any antibiotic to treat shipping fever in your cattle. The company claims that it is more effective and will save you money using this antibiotic. You will use the same type of feed, amount of water, health of the cattle, and age of the cattle. You will measure the temperature of the cattle’s fevers to see whether or not the new antibiotic works on treating shipping fever.
What are 4 control variables in this experiment?
To test just the brand of laundry detergent, the following variables would all need to be controlled:
type of feed
amount of water
- health of the cattle
age of the cattle
200
If you have a coordinate where both numbers are POSITIVE, in which quadrant would it be?
If both numbers are positive, it would be in quadrant I.
200
What are the coordinates for the point on this image?
(-9,5)
300
The higher the temperature of the water, the faster an egg will cook. What is the independent variable?
Temperature of the water.
300
Can a person run faster in tennis shoes or sandals?
What is the dependent variable in this experiment?
How fast they ran.
300
List four variables that would have to be controlled in the following experiment:
Which brand of laundry detergent will get a dirty spot out of clothes best?
To test just the brand of laundry detergent, the following variables would all need to be controlled:
Type of stain on clothes
How old the stain on the clothing is
Type of clothing the stain is on
The temperature of water used in the machine
The washing machine used
The cycle that the clothes are washed on in the machine
The amount of laundry detergent used
Place the laundry detergent is used (put in the water, put directly on the stain, etc.)
300
On a coordinate plane, the directions right and up are ______________, while the directions left and down are ____________.
On a coordinate plane, the directions right and up are positive, while the directions left and down are negative.
300
Which quadrant would the following coordinate be found in?
(-4,-2)
This coordinate would be in quadrant III because both numbers are negative.
400
Four groups of rats are first massed and then fed identical diets except for the amount of vitamin A they receive. Each group gets a different amount. After 3 weeks on the diet, the rats’ masses are measured again to see if there has been a decrease.
What is the independent variable?
The amount of Vitamin A.
400
Students measured the temperature of the water at different depths in Lake Skywalker and found that the temperature varied.
What is the Dependent variable?
The distance the skateboard travels on each surface.
400
List four variables that would have to be controlled in the following experiment:
Which brand of soda reacts the most with Mentos?
In order to test just the brand of soda, all of the following variables would need to be controlled:
The type of Mentos being use
The number of Mentos used
The container the soda is in (can or size of bottle)
The age of the sodaThe age of the Mentos
The temperature of the soda
The way the reaction is measured
The condition of the soda (not being shaken)
400
On this graph, the independent variable is _______ and is on the _____ axis, while the dependent variable is ______ and is on the _____ axis.
On this graph, the independent variable is the day of the month and is on the X axis, while the dependent variable is amount of rainfall in millimeters and is on the Y axis.
400
What are the coordinates for ALL 5 points on this graph?
A (4,3)
B (4,-3)
C (3,-5)
D (-4,-3)
E (-5,3)
500
A farmer wanted to know whether different amounts of water or different types of fertilizer would make his apple trees produce more apples. He decided to experiment with 40 apple trees divided into groups of 10. He gave 10 trees (Group A) no extra water and no extra fertilizer. He gave Group B 25% more fertilizer and water. He gave Group C 50% more fertilizer and water. He gave group D 75% more fertilizer and water. After 3 weeks, he picked the apples and tallied the number of apples produced by each group.
Did the farmer's experiment results help him? Was this experiment done correctly? Why or why not?
The results of the experiment did not help him. Because he gave the trees both extra water and fertilizer at the same time, he had two independent variables. After the experiment, he wouldn't know whether the water or the fertilizer had the biggest impact on the amount of apples produced. You can only have one independent variable.
500
Dr. Smith wants to examine whether a new drug increases the maze running performance of older rats. Just like aging humans, older rats show signs of poorer memory for new things. Dr. Smith teaches two groups of older rats to find a piece of tasty rat chow in the maze. One group of rats is given the new drug while they are learning the maze. The second group is not given the drug. One week after having learned the maze he retests the rats and records how long it takes them to find the rat chow.
What is the dependent variable in this experiment?
The dependent variable is how long it takes them to find the rat chow.
500
Which material makes the best insulator: plastic, metal, or Styrofoam?
In the experiment above, which type of variable would the size of the container be?
The size of the container is an example of a control variable. The material of the container changes but the size would need to be controlled or kept the same.
500
(3, -2, -9)
Why are there three numbers in this set of coordinates instead of just two? What axis do each of the numbers represent?
This is a 3 dimensional coordinate. It also includes information for depth (Z-axis).
3 is the X-axis value, -2 is the Y-axis value, and -9 is the Z-axis value.
500
In the following experiment data table, which column represents the X-axis (independent variable) and the Y-axis (dependent variable)?
Graph the data on a coordinate plane.
Hypothesis: If a plant is given too much water, then it will grow more slowly.
Experiment Data:
| Amount of water (ml) | Height of plant (cm) |
|---|---|
| 10 ml | 1 cm |
| 20 ml | 3 cm |
| 30 ml | 6 cm |
| 40 ml | 8 cm |
| 50 ml | 5 cm |
| 60 ml | 2 cm |
The amount of water in milliliters represents the X-axis because it is the independent variable. The Y-axis (dependent variable) is the height of the plant in centimeters. The person performing the experiment would change the amount of water given to the plant and the height of the plant would change depending on how much water it was given.
Graphing the data as just simple (x,y) coordinates would look like this:
