Reaction Time

• Measuring Reaction Time

  • The reaction time is defined as:A measure of how much time passes between seeing something and reacting to it
  • The human reaction time for someone who is alert is usually in the range of 0.2 - 0.9 seconds
  • e.g. someone waiting to react to something happening, like an athlete waiting for the start of a race
  • A simple method for measuring human reaction time is illustrated below:

  
• • A simple method for measuring human reaction time is illustrated below:

  
• • Person A holds a 30 cm ruler vertically, such that the bottom end of the ruler hovers over the top of the hand of Person B
  • Person A should release the ruler unexpectedly
  • As soon as Person B sees the ruler move, they should close their hand, catching it
  • The ruler is marked at the point at which it was caught by Person B - i.e. in line with the top of their hand
  • This gives a measurement of the distance the ruler fell
  • The greater the distance, the longer the reaction time