Reaction Time Calculator
Compute reaction time from measured catch distance of a dropped ruler.
How to Use This Calculator
1
Perform a ruler drop test
Drop a ruler between fingers without warning; measure the distance it fell before being caught.
2
Enter the distance
Use centimeters. Average multiple trials for accuracy.
Formula
t = \u221a(2d/g)
d is drop distance, g is gravitational acceleration.
Frequently Asked Questions
How accurate is this method?
It’s a rough estimate. Practice, anticipation, and measurement error affect results; average several trials.
Can I use other units?
Yes, but ensure d and g are consistent (e.g., meters and m/s²).