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When experimenting with the growth of a plant, a scientist uses three (of the same type of) plants, two different fertilizers, equal light, and equal water. What type of variable is the fertilizer?

• Dependent
• Independent
• Control

Tags

NGSS.MS-ETS1-1

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

Tags

NGSS.MS-PS3-5

Jessie is concerned about how tired his classmates seem. He created a drink that he thinks will boost their energy. He recruits 100 classmates with a history of tiredness. He has 50 of them drink his new special energy drink. The other 50 drink a beverage that looks like the special energy drink, but is just water and food coloring. Both groups were told that they were getting the special drink that would boost energy. After 2 hours, 30 classmates in the first group reported having more energy and 8 classmates in the second group reported having more energy.
What is the independent variable?

• Amount of energy
• Type of Drink
• The food coloring
• There isn't one

Jessie is concerned about how tired his classmates seem. He created a drink that he thinks will boost their energy. He recruits 100 classmates with a history of tiredness. He has 50 of them drink his new special energy drink. The other 50 drink a beverage that looks like the special energy drink, but is just water and food coloring. Both groups were told that they were getting the special drink that would boost energy. After 2 hours, 30 classmates in the first group reported having more energy and 8 classmates in the second group reported having more energy.
What is the dependent variable?

• Amount of energy
• 100 classmates
• Type of Drink
• There is none

What would the INDEPENDENT variable be in an experiment testing which types of paper airplane goes furthest?

• the paper used
• the type of paper airplane
• the distance of each plane's flight
• how hard the plane is thrown

A custodian notices some dirty tables and wants to know what's the best cleaner.  He uses a new spray cleaner to remove the green slime left by students on half of his tables and water on half of his tables.  Identify the independent variable.

• type of cleaner
• the new cleaner
• the green slime
• the effect of the cleaner

This part of the experiment serves as a basis of comparison; the one variable being tested has been omitted. 

• experimental group
• control group
• data
• variables

This variable in an experiment is the one being deliberately changed by the scientist. 

• dependent variable
• independent variable
• data
• control group

A comprehension test was given to students after they had studied textbook material either in silence or working together.
What is a possible control variable?

• Comprehension Test Results
• The thickness of the text book
• All students working in Silence
• Number of students working together and in Silence

For Julie to make 16 muffins, she need 2 cups of flour. To make 32 muffins she needs 4 cups of flour.  What is the dependent variable? 

• number of muffins
• cups of flour
• 16 muffins
• chocolate chips