Required Practical 7: Reaction Time

Study Notes

The text describes a method for measuring a person's reaction time in a practical experiment.
The experiment involves two people: person 1 has their reaction time measured by person 2, then they switch places.
Person 1 sits on a stool with upright posture and places their dominant arm across the table with their hand hanging over the edge.
Person 2 holds a ruler vertically with the zero centimeter mark between person 1's thumb and first finger.
Person 2 tells person 1 to prepare to catch the ruler and drops it at a random time. Person 1 catches the ruler with their thumb and first finger as quickly as possible and the reaction time is recorded.
The test is repeated several times and a mean is calculated.
The results can be converted to reaction time using a conversion table.
The independent variable in the experiment is the person having their reaction time measured, the dependent variable is the reaction time.
Control variables include keeping the working distance between thumb and first finger constant, measuring the ruler at the top of the thumb, and keeping the conditions in the room the same.
Other independent variables that could be investigated include the effect of practice, hand dominance, and chemicals such as caffeine.
To investigate the effect of caffeine, the test subject would consume a measured amount of Cola half an hour before the experiment.
Controls include checking for medical issues that could be affected by caffeine and conducting the test in a lab without hazardous chemicals.
Questions about the required practical can be found in the teacher's vision workbook.

Description

Learn about a practical experiment to measure a person's reaction time using a ruler and the key variables involved. Understand how to conduct the experiment, calculate the mean reaction time, make conversions, and investigate the effects of different independent variables such as practice, hand dominance, and caffeine.