REQUIRED PRACTICLE REFLEX

• Ruler drop test

  1. Work with a partner.
  2. Person A holds out their hand with a gap between their thumb and first finger.
  3. Person B holds the ruler with the zero at the top of person A's thumb
  4. Person B drops the ruler without telling Person A and they must catch it.
• 1. The number level with the top of person A's thumb is recorded in a suitable table. Repeat this ten times.
  2. Swap places, and record another ten attempts.
  3. You can use the conversion table to help convert your ruler measurements into reaction time or just record the catch distance in cm.
• Measuring a person's reaction time

  1. Person 1 sits on stool with good upright posture

  2. Person 1 places forearm of dominant arm across table with hand overhanging edge

  3. Person 2 holds ruler vertically with 0 cm mark between Person 1's thumb and first finger

  4. Person 2 tells Person 1 to prepare to catch ruler

  5. Person 2 drops ruler at random time

  6. Person 1 catches ruler with thumb and first finger as quickly as possible

  7. Person 2 records measurement on ruler level with top of Person 1's thumb

  8. Repeat test several times and calculate mean

  9. Switch roles, Person 1 tests Person 2's reaction time
• Independent variable

  The variable that is changed (the person having reaction time tested)
• Dependent variable

  The variable that is measured (the reaction time)
• Control variables

  • Constant stick working distance between thumb and first finger
  • Measure ruler at top of thumb
  • Keep conditions in room the same (lighting, background noise)
• Changing control variables could affect the dependent variable (reaction time)
• Other independent variables that could be investigated

  • Effect of practice (number of tries)
  • Dominant vs non-dominant hand
  • Effect of chemicals (e.g. caffeine)
• Need to check for any medical issues that could be affected by chemicals given to test subjects
• Carry out tests in a lab where hazardous chemicals are not normally used