1. Experimental Design

2. Observation Something you experience that makes you wonder and ask questions. Hmm... I heard a rumor that there is a ringtone that adults cannot hear

3. Ask a question Either ask a question or state a problem Can adults really not hear certain ringtones?

4. Hypothesis A tentative testable prediction of your observations based on prior experiences Format: If... then... because... age affects the frequency people can hear we play the ringtone for different ages older people won’t hear the higher frequency ringtone

5. Experiments Tests hypothesis Must be controlled – only one variable is purposefully changed Ten people of different ages are in the same room at the same time and are exposed to the mosquito ringtone from the same phone.

6. Parts of Controlled Experiment Independent Variable – variable that is changed by the experimenter Dependent Variable – variable that changes in response to the independent variable (what is measured) Independent variable: Age Dependent variable: if they hear the ringtone

7. Parts of Controlled Experiment Control Group – group that is used for comparison (normal group) Constants – parts of the experiment that remain the same for all trials Control Group – young people who hear the ringtone Constants – Same room, same time, same phone, same volume, same ringtone

8. Record Data & Analyze Qualitative data – word descriptions Quantitative data – numerical descriptions Analysis of data – looking for patterns, applying mathematical models, graphing Qualitative data – some adults don’t react when phone rings Quantitative data – 4 of the 5 people under 18 hear ringtone while only 1 of the 5 people 18 and older hear the ringtone Analysis of data – see graph

9. Age of Listener (years) Number of people who can hear the ringtone The Effectiveness of Mosquito Ringtones

10. Conclusion Reject or accept hypothesis based on results Based on our results, we would accept our hypothesis

11. So now what? Did we just make a new theory or law? NO. Theories are a set of related hypotheses that have been tested and confirmed many times by many scientists. Laws state rules of nature and are explained by theories.