Drugs affect the rate of our reactions depending on their properties. For example, depressants, like alcohol, slow us down. Therefore, drinking and driving is prohibited as well as driving after consuming more than the recommended amount of alcohol.
Other drugs, like caffeine, are stimulants, they make us alert. They are said to decrease our reaction time, which means when we have them, we react faster.
Athletes are tested prior to competitions. They are disqualified and not allowed to compete if they are found to have taken stimulants because this gives the athlete an advantage over other competitors.
You have to design an experiment to find out if stimulants decrease reaction times. The experiment must involve the time it takes to catch a ruler; this is how you will measure the reaction time.
Now let's work through a series of questions together, your answers will help you plan most of your experiment.
Over to you!