Required Practical 7: Reaction Time

• What should you be able to describe by the end of the video on measuring reaction time?


  How to measure a person's reaction time
• What is the method for measuring a person's reaction time?


  • Person 1 sits on a stool with good posture.
  • Person 1 places their dominant arm across the table.
  • Person 2 holds a ruler vertically at the zero mark.
  • Person 2 drops the ruler at a random time.
  • Person 1 catches the ruler with their thumb and first finger.
  • Measurement is recorded at the top of Person 1's thumb.
  • The test is repeated several times to calculate a mean.
• What position should Person 1 be in during the reaction time test?


  Person 1 should sit on a stool with good upright posture
• What does the dominant arm refer to in the context of the reaction time test?


  The dominant arm is the arm that a person uses most often, typically the right arm for right-handed individuals
• What should be positioned between Person 1's thumb and first finger when measuring reaction time?


  The zero centimeter mark of the ruler
• What is the role of Person 2 in the reaction time test?


  Person 2 drops the ruler and records the measurement
• Why is it important for Person 1 to have a short rest between tests?


  To ensure that their reaction time is not affected by fatigue
• What is calculated from the repeated measurements in the reaction time test?


  The mean reaction time
• How can results be converted to reaction time?


  Using a conversion table available on the Internet
• What happens after Person 1 completes their tests?


  Person 1 switches places with Person 2
• What is the independent variable in the reaction time experiment?


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


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


  • Distance between thumb and first finger should be constant
  • Ruler measurement should always be at the top of the thumb
  • Room conditions (lighting and background noise) should remain the same
• Why is it important to keep control variables constant in the reaction time experiment?


  To ensure that the reaction time is not affected by external factors
• What are some other independent variables that could be investigated in the reaction time experiment?


  • Effect of practice on reaction time
  • Effect of dominant vs. non-dominant hand
  • Effect of chemicals like caffeine on reaction time
• How could practice affect reaction time in the experiment?


  Reaction time may become shorter with more practice
• How can the effect of hand dominance be tested in the reaction time experiment?

  By testing reaction time with both the dominant and non-dominant hand
• How can caffeine be tested for its effect on reaction time?


  By having subjects drink a measured amount of cola before the experiment
• What precaution should be taken when testing subjects with caffeine?


  Check for any medical issues that might be affected by caffeine
• Where should the reaction time test be conducted?


  In a lab where hazardous chemicals are not normally used
• What resources can help with questions on the required practical?

  • Vision workbook
  • Link provided in the video