LN # 1Scientific Methods

Science

The word science comes from the Latin verb meaning “to know”.

In science observations lead to questions about the natural world.

The questions need to be answered with evidence that can be measured or observed.

Hypothesis

Observations lead to hypothesis. A hypothesis is a temporary explanation for a

question or a problem. Hypothesis are not proven they are

supported or rejected based on experimental results.

A hypothesis can be changed or modified. Scientist design experiments that could

possibly reject their hypothesis.

Experiments

An experiment is used to test a hypothesis. An experiment needs to be designed in a way

that it can be repeated. Also the results need to be clear.

Designing an Experiment

An experiment has a control group and an experimental group.

The control group and the experimental group have all conditions the same except for the condition being tested.

The conditions that are kept the same are called constants.

The control group is important because the results of the experimental group are compared to the control group.

Independent and Dependent variables

In a controlled experiment only one factor is changed, this is called the independent variable.

The independent variable affects the outcome of the experiment.

The dependent variable is the effect caused by the independent variable.

The dependent variable is measured to obtain experimental results.

Theories and Laws

A theory comes from continued verification of a hypothesis.

A theory is supported by a large amount of evidence.

Theories are widely accepted. Laws are facts of nature. The words theory and law can be used

interchangeably. Newton’s theory of gravity is also called the law of gravity.

Summary

Write an 8 sentence summary about the lecture notes.

Your summary should answer the following:1. How do scientist answer questions?2. What is a hypothesis?3. What are experiments used for?4. What two groups are needed in an experiment?5. What are constants?6. What is an independent variable?7. What is a dependent variable?8. What is a theory?