Reaction time

• What is the aim for this practical?

  To measure how quickly a person reacts to a stimulus.
• The steps:

  • One person holds a ruler vertically above another's hand.
  • Without warning, drop the ruler.
  • Record the distance the person catches it at.
  • Convert distance into reaction time using a table.
• What is the independent variable?

  Caffeine intake or distractions (if tested).
• What is the dependent variable?

  Reaction time (distance ruler falls).
• What is the control variable?

  Same ruler, same person, same position.