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- dollar_drop_activity.gif

Credits

Author: Leong Tze Kwang
Contact: leongtzekwang@gmail.com

 To show that dollar drop has negligible air resistance for the 1st 0.3 second of the drop and can be used to determine human reaction time.

Document Brief: Title: "Tracker Reaction Time: 50 Dollars Note Drop"

This document explores the concept of human reaction time through the 50-dollar note drop experiment. By analyzing the time taken to catch the falling note, the study provides insights into neural response and reflexes.

Study Guide:

Objective: Measure and analyze reaction time using a simple and practical experiment involving a falling 50-dollar note.

Key Concepts:

1. Reaction Time:

   • The interval between the presentation of a stimulus (release of the note) and the response (catching it).

2. Free Fall:

   • The note accelerates under gravity () as it falls.

3. Neural Response:

   • Reaction time reflects the efficiency of sensory input, neural processing, and motor output.

Experiment Overview:

• Setup: Hold a 50-dollar note vertically between the thumb and forefinger of a participant's hand. Ensure the hand is positioned to catch the note as it falls.

• Procedure:

  • Without warning, release the note and measure the time or distance it falls before being caught.

  • Use the equation to calculate reaction time, where is the distance fallen and is the acceleration due to gravity.

• Observation Points:

  • The distance the note falls before being caught.

  • Variation in reaction times among different participants.

Questions to Consider:

1. How does reaction time vary among individuals?

   • Answer: Reaction time depends on factors like age, alertness, and practice. Younger individuals and those with faster reflexes tend to have shorter reaction times.

2. How is reaction time calculated in this experiment?

   • Answer: By measuring the distance and using the equation .

3. What factors can influence reaction time?

   • Answer: Distractions, fatigue, and anticipation can affect the outcome.

Applications:

• Understanding neural response times in humans.

• Testing reflexes in educational or medical settings.

• Highlighting the importance of reaction time in activities like driving and sports.

FAQ:

1. Why use a 50-dollar note? The note’s dimensions and weight make it ideal for this simple and practical demonstration.

2. What does the experiment demonstrate? It showcases human reaction time and the factors influencing it, such as alertness and focus.

3. Can this be applied to real-life scenarios? Yes, reaction time is critical in many daily activities, including driving, sports, and emergency responses.

4. How accurate is the measurement? While not highly precise, the experiment provides a good approximation of reaction time, especially when repeated and averaged.

5. What variations can be introduced? Using different objects or testing under varied conditions (e.g., distractions or different hand positions) can provide additional insights.