Reaction Time Experiment Lecture Notes

Introduction

• Presenter: Mr. Clifford
• Topic: Required practical of reaction time for combined science and GCSE.
• Definition: Reaction time is the time taken to respond to a stimulus.

Experiment Overview

• Objective: Investigate the effect of caffeine on reaction time.
• Hypothesis: Caffeine, being a stimulant, should increase reaction time.

Methodology

• Variable: Reaction time (measured in milliseconds).
• Independent Variable: Caffeine consumption (none vs. some caffeine).
• Control Variables:
  • Arm position
  • Person receiving the ruler
  • The ruler itself
  • Height of the drop
  • Amount of caffeine

Data Collection

• Results table:
  • Columns: Try number, Distance, Time (in milliseconds)
  • Two conditions: No caffeine vs. with caffeine

Practical Demonstration

• Subject: Mr. Tucker
• Procedure:
  • Mr. Tucker drinks coke (caffeine source).
  • Wait 20 minutes post-ingestion to test reaction time.
  • Measure reaction using a ruler drop above fingers.
• Measurements Without Caffeine:
  • Example Results: 202 ms, 212 ms
• Measurements With Caffeine:
  • Example Results: 163 ms, 192 ms

Conclusion

• Findings:
  • Reaction time was quicker after caffeine ingestion.
  • Shorter distance in the ruler drop corresponds to quicker reaction time.
  • Caffeine had a noticeable stimulating effect on reaction time.
• Data Interpretation:
  • Reaction time with caffeine (e.g., 163 ms, 192 ms) is less than without caffeine (e.g., 202 ms, 212 ms).
  • Confirms hypothesis that caffeine reduces reaction time.