SCIENTIFIC METHOD

SCIENTIFIC METHOD• If you put a golf ball in a beaker of water will it

float?• No, it will not. But if you put a golf ball in a beaker

of saltwater will it float?• Yes, it will, why?• Your explanation would be called a Hypothesis• Hypothesis – a statement that explains

observations and can be tested.• Not a prediction

THE SCIENTIFIC METHOD • How much salt is required to make the golf ball

float (tablespoons).• Hypothesis?• Ex. In 200 ml of water it will take 5 dissolved

tablespoons of salt to make the golf ball float.

STEPS

• Experiment – process of testing a hypothesis by gathering data under controlled conditions.

• All experiments have 2 groups:• 1. Control Group• 2. Experimental Group

• For our example: Golf ball in a beaker of water would be the control group and the experimental group is the golf ball in the beaker of water that is getting salt added to it, to make it float.

• Compare the control group and experimental group (identical except for one factor).

EXPERIMENT PARTS

• Independent variable – factor that is different between the control group and experimental group.• Ex. the amount of salt in the water

• Dependent variable – an observed or measured factor in both groups.• Ex. how much the golf ball floats

DATA TYPES• Observing – using the 5 senses to perceive

objects or events.

• Inference – conclusion made on the basis of facts rather than direct observations• Ex. If you see smoke you think

SCIENTIFIC METHOD

• Sampling – using part of a population to represent the whole (needs to be large and random).• Ex. 1,000 people, a sample would be 200.

EXPERIMENT PART

• Analyzing Data – determine if the data is reliable, does it support or disprove the hypothesis.

• A good scientist tries to disprove his hypothesis.

TYPES OF CONCLUSIONS

• Theory – a broad and comprehensive statement of what is thought to be true.• Formed after repeated testing of hypotheses

thru experiments.