Comp Science 2 - CFE Review- Nature of Science

How many variables can be changed in a controlled experiment?

• only one variable can be changed 
• there are no variables
• as many variables can change if needed
• three variables should be changed

If I want to know how much sunlight produces the healthiest roses.  What should be my independent variable?

• the height the roses grow
• the amount of water they recieve
• the amount of sunlight
• how my green leaves the roses have

Hurricane Irma will cause a great deal of beach erosion.  To demonstrate this I could pour water on a mountain of sand then measure the effects.  What is my dependent variable?

• how much water is used
• the height of the water being poured
• how tall the sand mountain started 
• the amount of sand lost from the erosion

Jordan thinks that different liquids will freeze at different rates.  He pours 3 ounces of soda into a cup, 3 ounces of milk into a cup, and 3 ounces of water into a cup.  What should he do next?

• Jordan should place each cup in the microwave and time how low it takes to get hot
• Jordan should put one cup in the freezer, one in the refrigerator, and one on the counter
• Jordan should put two in the freezer and leave one on the counter as the control
• Jordan should put all three in the freezer and record the time each one froze

Dylan like to watch lizards.  He wanted to know if lizards were social or independent animals. For 4 hours he watched the lizards interact in his backyard.  What kind of investigation did Dylan conduct?

• Dylan was did not conduct an investigation
• Dylan conducted a controlled experiment
• Dylan conducted a systematic observation
• Dylan was just playing around

A science class was investigating how far a ball could be thrown. The table below shows their results.

Trial Distance traveled by ball (m)

1. 10.2
2. 10.3
3. 10.5
4. 5.0

Based on the class’s data, how can they improve the accuracy of the investigation?

• Do more trials.

• Use a different ball

• Omit trial 4 from the data.

• Average the data to account for the short distance in trial 4

 In a controlled experiment, the variable that is changed to test the hypothesis is called the –

• Controlled Variable
• Responsive Variable
• Dependent Variable
• Independent Variable

The measurable factor in an experiment is known as the: 

• Control
• Independent Variable
• Constant
• Dependent Variable

When a another scientist does someone's experiment to see if the results are valid?

• repetition
• replication
• experimental method
• controlled variable

Caira reads in a science journal that replication and repetiton are so important, but she did not understand the  difference between them. Which of the following best explains the two terms?

• Repetition is when a scientist repeats an experiment; replication is when a scientist conducts an experiment on genetic material.
• Repetition is when a scientist does the same experiment a number of times; replication is when other scientists reproduce a scientist’s experiment.
• Repetition is when a scientist publishes in more than one scientific periodical; replication is when another scientist reproduces another scientist’s results.
• Repetition is when a scientist commits an error in an experiment the first time and must repeat it; replication is when a scientist repeats an experiment to make sure it is valid.