Case Study
In 1991, two hikers discovered the remains of a man in a melting glacier on the border between Austria and Italy.
Controlled experiments were needed to unravel the mystery of who the Iceman was.
When scientists design a controlled experiment, they have to identify factors that might affect the outcome.
A variable is any factor that can have more than one value.
The independent variable is the factor that you want to test. It is changed by the investigator to observe how it affects a dependent variable.
The dependent variable is the factor you observe or measure during an experiment.
When the independent variable is changed, it causes the dependent variable to change.
A controlled experiment has two groups.
Scientists concluded that the Iceman is about 5,300 years old.
The Iceman traveled from the high alpine region in spring to his native village in the lowland valleys.
There, during a conflict, the Iceman sustained a fatal injury.
He retreated back to the higher elevations, where he died.
Scientists recognize their hypotheses can never be proved, only supported or not supported.
With advances in technology, scientists are able to more thoroughly investigate mysteries of nature.
Controlled experiments were needed to unravel the mystery of who the Iceman was.
When scientists design a controlled experiment, they have to identify factors that might affect the outcome.
A variable is any factor that can have more than one value.
The independent variable is the factor that you want to test. It is changed by the investigator to observe how it affects a dependent variable.
The dependent variable is the factor you observe or measure during an experiment.
When the independent variable is changed, it causes the dependent variable to change.
A controlled experiment has two groups.
- The experimental group is used to study how a change in the independent variable changes the dependent variable.
- The control group contains the same factors as the experimental group, but the independent variable is not changed.
Scientists concluded that the Iceman is about 5,300 years old.
The Iceman traveled from the high alpine region in spring to his native village in the lowland valleys.
There, during a conflict, the Iceman sustained a fatal injury.
He retreated back to the higher elevations, where he died.
Scientists recognize their hypotheses can never be proved, only supported or not supported.
With advances in technology, scientists are able to more thoroughly investigate mysteries of nature.
