reaction time

• What should you be able to do by the end of the video?

  Describe how to measure reaction time
• What is the method for measuring reaction time?

  • Two people work together
  • Person 1 sits upright on a stool
  • Person 1's dominant arm is placed over the table
  • Person 2 holds a ruler vertically
  • Ruler is dropped randomly
  • Person 1 catches the ruler
  • Measurement is recorded at the thumb's top
  • Repeat the test and calculate the mean
• What position should person 1 be in during the test?

  Upright on a stool
• How should person 1's dominant arm be positioned?

  Across the table with hand overhanging
• What should person 1 do when the ruler drops?

  Catch it with thumb and first finger
• Where should the zero centimeter mark of the ruler be placed?

  Between person one's thumb and first finger
• What does person 2 do before dropping the ruler?

  Tells person 1 to prepare to catch
• How is the measurement recorded?

  At the top of person one's thumb
• What happens after the first test?

  Person one has a short rest
• Why is it important to repeat the test several times?

  To calculate a mean reaction time
• What do the two people do at the end of the test?

  Switch places for testing
• What is the independent variable in this experiment?

  The person having their reaction time tested
• What is the dependent variable in this experiment?

  The measured reaction time
• What are control variables in an experiment?

  Variables that are kept constant
• What are the control variables in this experiment?

  • Distance between thumb and finger
  • Measurement at the top of the thumb
  • Consistent room conditions (lighting, noise)
• What could happen if control variables change?

  It could affect the reaction time
• What are some other independent variables to investigate?

  • Effect of practice on reaction time
  • Hand used to catch the ruler
  • Impact of chemicals like caffeine
• How could practice affect reaction time?

  It may shorten reaction time with more tries
• How can the dominant hand affect reaction time?

  Dominant hand may have shorter reaction time
• How can caffeine affect reaction time?

  It may improve reaction time
• What should be done before testing with caffeine?

  Check for medical issues affecting caffeine
• Where should the test be conducted?

  In a lab without hazardous chemicals
• Where can students find questions on this practical?

  • In the vision workbook
  • Available via a provided link