Science Scenarios

Independent vs Dependent Variables

Independent Variables:

1.  What the experimenter CHANGES

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Example: The amount of water changes depending on how

much ​the plant needs

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Some text here about the topic of discussion

​Dependent Variables:

1. ​What the experimenter is MEASURING

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Example: The size of the plant is being measured by the experimenter

Some text here about the topic of discussion

Constants:

1. ​Some factors in are experiment are kept the same:

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Example: number of plants in the experiment, type of soil, amount of sunlight

Some text here about the topic of discussion

Multiple Choice

An independent variable is what the experimenter ____________.

• Measures

• Changes

Multiple Choice

A dependent variable is what an experimenter is _____________.

• Measuring

• Changing

Multiple Choice

What are constants?

• Things you keep the same- they do not change

• What you observe or measure

• What you decide to change in an experiment

Multiple Choice

Sam wants to see which cat food brand his cat, Misty, likes best. He tests three different brands. Each morning he picks a different brand, and gives Misty one cup.  Then, Sam records how much food Misty has eaten.

What is the independent variable (IV)?

• IV = amount of cat food eaten

• IV = Misty the cat

• IV = one cup of cat food

• IV = brand of cat food

Multiple Choice

Sam wants to see which cat food brand his cat, Misty, likes best. He tests three different brands. Each morning he picks a different brand, and gives Misty one cup.  Then, Sam records how much food Misty has eaten.

What is the constant?

• constant = amount of cat food eaten

• constant = one cup of cat food

• constant = brand of cat food

Multiple Choice

Kenley wonders how the color of light will affect plant growth. She places one plant under blue light; one under green and one in natural light. At the end of the month she measures each plant to see how tall it is.

What is the dependent variable (DV)?

• DV = the type of plant

• DV = the plant under natural light

• DV = height of the plant

• DV = color of the light

What Is A Hypothesis?

• It's a prediction

• It's an educated guess

• It's a testable explanation to a question

• It's an If...Then statement

​Your hypothesis is an educated guess about what will happen when you do your experiment

When Writing A Hypothesis

• First, write If... followed with the independent variable

• Next, write Then... followed with the dependent variable

• Because....why you think that (based on your research)​

Multiple Choice

Possible explanation for an observation that can be tested.

• Hypothesis

• Scientific Law

• Scientific theory

• Critical Thinking

Multiple Choice

What two words should be in your hypothesis?

• I think

• If ...then...

• It will

• No idea

Multiple Choice

When writing your hypothesis, what information follows IF?

• dependent variable

• how you know it will happen

• independent variable

• anything

Multiple Choice

When writing a hypothesis, what information do you fill in after THEN?

• dependent variable

• independent variable

• how you know it will happen

• anything good

Multiple Choice

Choose the correct hypothesis for "What effect does studying have on your test grade?"

• IF I study for hours, THEN my test grade will be better.

• IF I have a good test grade, THEN I will study.

• Good grades are from studying.

Multiple Choice

A students was doing an experiment using the scientific method. Every three days the student plans to count the green leaves. Which would be a good hypothesis for this experiment?

• If plants are placed in direct sunlight, then they will grow more green leaves.

• If plants are places in bright light, then they will grow more green leaves than in dim light.

• If plants are place in clay pots, then they will grow more green leaves than plastic pots.

• If plants are in warmer temperatures, then they will grow more green leaves.

Multiple Choice

Choose the correctly written hypothesis for "What is the effect of putting Pam Cooking Spray on the bottom of a sled?"

• I think the sled will slide faster.

• If I put Pam Cooking Spray on the bottom of my sled, then I will win the race."

• If I put Pam Cooking Spray on the bottom of my sled, then I will slide faster.

Multiple Choice

Students want to test if changing the wing shape of a paper airplane  will affect  the distance it  will fly. What is the independent variable? 

• the wing shape 
• the distance the airplane will fly 
  dependent
• the temperature in the classroom 
• the type of paper used to construct the plane 

Multiple Choice

Students want to test if changing the wing shape of a paper airplane  will affect  the distance it  will fly. What is the dependent variable? 

• the wing shape 
• the distance it will fly 
• the temperature in the room 
• the type of paper used to construct the airplane 

Multiple Choice

Students want to test if changing the wing shape of a paper airplane  will affect  the distance it  will fly. Which of the following is a good hypothesis for this experiment? 

• If the airplane fly for three minutes, then that will be the best design 
• If the wing shape is round, then the airplane will fly for more time 
• If the wing shape is wider, then the airplane will covered more distance 
• If the airplane is made of construction paper, then it will fly farther