How Sceince Works

Question 1

What is a possible explanation for something?

Answer 1

A theory.

Question 2

A simplified picture of what’s going on?

Answer 2

A model.

Question 3

A specific testable statement, based on a theory, about what will happen in a test situation.

Answer 3

Prediction or hypothesis.

Question 4

How might you validate a theory? (2)

Answer 4

Repeat the exact experiment.

Using a theory to make a new prediction then testing it with new experiments.

Question 5

What is it important to control in order to draw meaningful conclusions?

Answer 5

Variables.

Question 6

What results will a good experiment provide? (4)

Answer 6

Precise - Results don’t vary much from the mean.

• *Repeatable** (same methods and equipment)
• *Reproducible** (slightly different method or equipment)

Valid - Results answer the original questions. Variables have been controlled.

Accurate - Results are very close to the true answer.

Question 7

What are the variables?

What are the two types of variables?

Answer 7

Quantities that have the potential to change.

• *Independent variable** - the one you change
• *Dependent variable** - the one you measure.

Question 8

Three types of controls?

Answer 8

Negative - aren’t expected to have any effect on the experiment.

Positive - Shows that a positive result should look like.

Control groups - subjects in a study are split into two groups.

Question 9

Apart from repetition, how might you improve test results?

Answer 9

Increase the sample size to reduce the likelihood that results are due to chance.

Question 10

What does a negative control show?

Answer 10

That only the independent variable is affecting the dependent variable.

Question 11

What three things should you consider when carrying out a risk assessment?

Answer 11

1) Dangers
2) Who is at risk
3) How can the risk be reduced