Physics GCSE
reaction time
What reaction time means in Physics GCSE, as defined for AQA, OCR.
Definitions of reaction time
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Reference: OCR
The delay between a stimulus and a response, measured in humans using methods such as the ruler drop.
Lengthened by tiredness, alcohol or a phone, and so the thinking distance is lengthened too.
Around 0.2 s for a human, and the main source of random error when timing a short interval.
Topics that use reaction time
- Factors affecting braking distance 1 (AQA GCSE)
- Speed (AQA GCSE)
- Physics on the move (OCR GCSE)
Related terms
- speed of sound in air
- average speed
- braking distance
- constant speed
- distance equation
- distance travelled
- emergency stopping
- Everyday transport speeds
Using reaction time in the exam
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