The Hypothesis-Variable Wrap

Variables & Hypotheses

​The Wrap Up

The Wrap Up

​There are 3 main types of variables

• ​Independent variable - The variable that is changed by the researcher

• ​Dependent variable - The variable that is measured

• ​Controlled variable or constant - Any variable that is kept the same so it won't affect the outcome

A hypothesis is a tentative, testable answer to a scientific question that often takes the shape of an "If ____then ____" statement and can be tested by experimenting. Hypotheses are basically predictions that include both the  independent variable and dependent variable​. While there can be multiple dependent variables, there can only ever be one independent variable.

Multiple Choice

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music. In this investigation, the independent variable is ...

• The type of plant
• The amount of sunlight
• The type of music
• The type of liquid

Multiple Choice

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music. In this investigation, what is the dependent variable?

• Type of plant
• Water, apple juice, milk
• Plant growth

Multiple Choice

A student is planning an experiment to find out how the height from which he drops a ball affects how high the ball bounces. The dependent variable is the _____.

• Diameter of the ball
• Force acting on the ball
• Height that the ball bounces
• Height from which the ball is dropped

Multiple Choice

Lauren is convinced that book/movie combinations are better if you have read the book before watching the movie. Lauren's friend, Alyssa, thinks that movies are just as good even if you don't read the book. They got 40 of their classmates to help them solve their debate. 20 classmates read the book Divergent and 20 more classmates viewed the movie without reading the book. All participants went to see the movie on Friday at 6 p.m. They had their classmates do a survey (1-4 stars). Then, Alyssa and Lauren averaged the number of stars for both groups.
What is the dependent variable?

• The length of the movie
• The time the movie starts
• The # of stars the movie gets

Multiple Choice

Mr. S set up an experiment to see how the mass of a ball affects the distance it rolls off a ramp. What is the controlled variable?

• Distance traveled by the ball
• Height of the ramp
• Mass of the ball

Multiple Choice

How does the amount of fertilizer affect the height of a plant? The independent variable is

• the height of the plant

• the amount of fertilizer

Multiple Choice

In a study to determine how the TEMPERATURE OF THE ROOM impacts a PLANT'S GROWTH, the INDEPENDENT variable is...

• amount of growth

• type of plant

• the temperature of the room

• amount of light

Multiple Choice

A scientist is testing the impact of light and dark on the moth behavior by turning a light on and off. The DEPENDENT variable is...

• amount of light

• moth behavior/their reaction

• number of moths

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

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

Which one is a good hypothesis?

• If we mix blue and yellow water together, the water will turn green.

• We'll mix blue and yellow water together, then the water will turn green.

• If we mix blue and yellow water together, then the water will turn green.