Homeostasis & ResponseRequired Practical
Required Practical: Measuring Reaction Time (RPA7)
Part of Reflex Arc — GCSE Biology
This required practical covers Required Practical: Measuring Reaction Time (RPA7) within Reflex Arc for GCSE Biology. Topic 3: Reflex Arc It is section 4 of 14 in this topic. Revise both the method and the reason for each step, because practical questions often test understanding rather than pure recall.
Topic position
Section 4 of 14
Practice
15 questions
Recall
20 flashcards
🧪 Required Practical: Measuring Reaction Time (RPA7)
In this practical, you measure reaction time using the ruler-drop method:
- One person holds a ruler vertically at the 0 cm mark between another person's open thumb and forefinger.
- The ruler is dropped without warning — the second person catches it as quickly as possible.
- Read the distance the ruler fell (in cm) and use a conversion table to find the reaction time.
- Repeat at least 5 times and calculate the mean to improve reliability.
Variables: Independent = factor being tested (e.g. caffeine, practice). Dependent = distance ruler falls. Control = same ruler, same hand, same starting position.