Scientific Method review

Scientific Method review

Independent Variables

A independent variable is the variable that the experimenter purposes changes or manipulates. The independent variable is the cause, input, or what is being done during the experiment.

Dependent Variables

A dependent variable is the variable that changes in response to the changes in the independent variable. The dependent variable is the effect, output, or what happens during the experiment.

Control variables (constant variables)

these are the elements that are kept the same during a scientific experiment. Any change to a controlled variable would invalidate the results.

Read the problems and identify the independent, dependent variable in each as well as constant variables.

Multiple Choice

The higher the temperature of the water, the faster the egg will boil. What is the Independent variable? (The 'cause' in a 'cause-effect' relationship)

• The temperature of the water

• The egg

• The time the egg takes to boil

• The type of egg

Multiple Choice

The higher the temperature of the water, the faster the egg will boil. What is the dependent variable (the effect)

• The egg

• The temperature of water

• The type of water

• The time it takes the egg to boil

Multiple Choice

Students of different age groups were asked to put the same jigsaw puzzle together, they were timed to see how long it took. What is the dependent variable?

• Age of students

• The jigsaw puzzle size

• The time to complete puzzle

• The music they listened to

Multiple Choice

Students of different age groups were asked to put the same jigsaw puzzle together, they were timed to see how long it took. What is the independent variable?

• The age of the student

• The jigsaw puzzle

• The time to complete puzzle

• The music they listened to

Open Ended

Do tomatoes grow fastest under fluorescent, incandescent, or natural light? What is the independent variable?

Open Ended

Do tomatoes grow fastest under fluorescent, incandescent, or natural light?

What is the dependent variable?

Open Ended

Do tomatoes grow fastest under fluorescent, incandescent, or natural light?

List as many constant variables that you can think of.

Open Ended

How does phone use before bedtime affect sleep?

What is the dependent variable?

Multiple Choice

Albanee is performing a test in which she is trying to see if plants can grow when given fizzy drinks instead of water. She gives one plant water and a second identical plant the same amount of fizzy drink for two weeks. What is the independent variable?

• The plants

• The amount of liquid

• The type of liquid

• Sally

Multiple Choice

Albanee is performing a test in which she is trying to see if plants can grow when given fizzy drinks instead of water. She gives one plant water and a second identical plant the same amount of fizzy drink for two weeks.

What is the dependent variable?

• The plants' growth

• The amount of liquid

• The type of liquid

• Sally

Multiple Select

Albanee is performing a test in which she is trying to see if plants can grow when given fizzy drinks instead of water. She gives one plant water and a second identical plant the same amount of fizzy drink for two weeks.

What are two constant variables from the experiment?

• The type of plants

• The amount of liquid

• The type of liquid

• The plants' growth

Open Ended

Sam carried out an investigation to see how the strength of an electromagnet coil changes with the number of coils. What is the dependent variable?

Question: Do different types of music affect how well a person can do his/her homework?

Hypothesis: Music that does not have a strong beat makes concentrating on a homework assignment easier. Music with heavy beats makes concentration more difficult. 

Open Ended

David pulled out four different CD’s to find out which type helped him to finish his homework the fastest. The first CD was rock, the second rap/hip-hop, the third classical, and the fourth was country. He chose a math assignment that required concentration. David used a stopwatch with an alarm to make sure that he only listened to each CD for 5 minutes. Each time the alarm went off, he recorded how many problems he was able to finish. Identify the:

Independent Variable (IV)

Dependent Variable (DV)

Constant Variables (list two)

Open Ended

Type of music - Problems (quantified data)

Classical - 7

Rock - 5

Country - 4

Rap/hip-hop - 2

Summarize the results of David's experiment

Poll

How would you rate yourself in 'differentiating between the independent and dependent variables?'

• Got it, can help someone else get it!!

• Think I got it, may need to practice more with a quizizz

• I need more help than practice

• I got nothing