Biology Practical: Reaction Time Measurement

Objective

• To measure and calculate the reaction time of an individual using a simple experimental setup.

Materials Required

• Chair
• Meter ruler
• Table
• Partner
• Conversion table (to convert ruler measurements to reaction time)

Key Concepts

• Reaction Time: The duration it takes for someone to respond to a stimulus.
  • Important in biology and physics (e.g., driving and stopping distances).
  • A quick reaction time means a shorter time to respond to a stimulus.

Procedure

1. Setup

   • Use your weaker hand (non-dominant hand).
   • Place your forearm on the table with thumb and forefinger over the edge.
   • Ensure you are looking at a wall and using peripheral vision to detect the ruler.

2. Ruler Drop Test

   • Partner holds the ruler vertically above your forefinger and thumb.
   • Zero mark of the ruler should be just above your forefinger.
   • Partner randomly drops the ruler.

3. Data Collection

   • Close fingers on the ruler as soon as you detect it moving.
   • Record the distance the ruler traveled.
   • Repeat the test a total of 10 times, taking short rests between trials.

4. Data Analysis

   • Convert the measured distances into reaction times using a conversion table.
   • Calculate the average reaction time.

Results and Observations

• Example result: 18 cm recorded into the table.
• Average reaction time calculated: 0.17 seconds.

Variations and Comparisons

• Swap roles with your partner to compare reaction times.
• Compare reaction times before and after consuming stimulants like caffeine or sugar.
• Compare results with classmates.

Important Insights

• Reaction time is crucial in everyday tasks and safety considerations such as driving.
• Better or faster reaction time is indicated by a shorter measurement, meaning quicker responses to stimuli.

Practical Tips

• Avoid distractions during the experiment.
• Utilize peripheral vision effectively.
• Ensure randomness in the ruler drop to maintain accuracy in results.