Experimental Variables

L.E: Experimental Variables

IV, DV, Constants

Different Types of Variables

• Independent Variable/IV: The variable you change between the setups (the thing you manipulate)

• Dependent Variable/DV: The variable you are measuring/recording as data (the thing responding to the IV)

• Constants: The variables that are the same in all setups

Cindy's Experiment

Cindy wants to know if hand sanitizer prevents mold from growing. She uses 2 pieces of white bread. She touches one piece with unclean hands and the other piece with sanitized hands. Then she puts each piece in a bag and leaves them on a window sill.

Open Ended

Considering her question, write a hypothesis that Cindy might be testing.

Multiple Choice

Cindy wants to know if hand sanitizer prevents mold from growing. She uses 2 pieces of white bread. She touches one piece with unclean hands and the other piece with sanitized hands. Then she puts each piece in a bag and leaves them on a window sill.

What is her independent variable?

• the amount of mold that grows

• whether or not sanitizer is used

• what type of bread she used

• the bread touched with unclean hands

Multiple Choice

Cindy wants to know if hand sanitizer prevents mold from growing. She uses 2 pieces of white bread. She touches one piece with unclean hands and the other piece with sanitized hands. Then she puts each piece in a bag and leaves them on a window sill.

What is her dependent variable?

• the amount of mold that grows

• whether or not sanitizer is used

• what type of bread she used

• the bread touched with unclean hands

Multiple Select

Cindy wants to know if hand sanitizer prevents mold from growing. She uses 2 pieces of white bread. She touches one piece with unclean hands and the other piece with sanitized hands. Then she puts each piece in a bag and leaves them on a window sill.

What were the constants in her experiment? (check all that apply)

• same type of bread used

• one was touched with sanitizer, one wasn't

• both were placed in a baggie

• both were placed on a window sill

Open Ended

Cindy wants to know if hand sanitizer prevents mold from growing. She uses 2 pieces of white bread. She touches one piece with unclean hands and the other piece with sanitized hands. Then she puts each piece in a bag and leaves them on a window sill.

Identify her control group

Open Ended

What data/results would support the claim that hand sanitizer does prevent mold from growing?